Collect | Home Page 
   
Office Online  
Journal Online
· Forthcoming Articles
· Current Issue
· Archive
· Advanced Search
· View by Fields
· Archive By Subject
· Special Issues
· Download Articles
· Read Articles
· Email Alert
· Recommended
Links
·
·
·
·
·
·
·
·
·
·
·
   Science & Technology Review
2010, Vol.28, No. 14
28 July 2010

Articles
Reviews
Focus
Select | Export to EndNote
卷首语

On the Concepts of "Green" and "Low Carbon"

Science & Technology Review. 2010, 28 (14): 3-3. ;  doi:
Full text: HTML (0 KB)  PDF  (230 KB)  ( 208 )
Abstract ( 349 )
特别栏目

Science & Technology Review. 2010, 28 (14): 8-8. ;  doi:
Full text: HTML (0 KB)  PDF  (451 KB)  ( 185 )
Abstract ( 326 )

Science & Technology Review. 2010, 28 (14): 10-10. ;  doi:
Full text: HTML (0 KB)  PDF  (328 KB)  ( 140 )
Abstract ( 329 )

Science & Technology Review. 2010, 28 (14): 14-15. ;  doi:
Full text: HTML (0 KB)  PDF  (383 KB)  ( 151 )
Abstract ( 308 )

Science & Technology Review. 2010, 28 (14): 16-17. ;  doi:
Full text: HTML (0 KB)  PDF  (837 KB)  ( 145 )
Abstract ( 335 )

Science & Technology Review. 2010, 28 (14): 18-19. ;  doi:
Full text: HTML (0 KB)  PDF  (302 KB)  ( 145 )
Abstract ( 311 )

Science & Technology Review. 2010, 28 (14): 20-20. ;  doi:
Full text: HTML (0 KB)  PDF  (1779 KB)  ( 141 )
Abstract ( 327 )

Science & Technology Review. 2010, 28 (14): 127-127. ;  doi:
Full text: HTML (0 KB)  PDF  (924 KB)  ( 170 )
Abstract ( 326 )

Science & Technology Review. 2010, 28 (14): 140-140. ;  doi:
Full text: HTML (0 KB)  PDF  (667 KB)  ( 171 )
Abstract ( 295 )
封面图片说明

Science & Technology Review. 2010, 28 (14): 8-8. ;  doi:
Full text: HTML (1 KB)  PDF  (451 KB)  ( 136 )
Abstract ( 290 )
半月科技风云

Science & Technology Review. 2010, 28 (14): 9-9. ;  doi:
Full text: HTML (0 KB)  PDF  (107 KB)  ( 236 )
Abstract ( 343 )
科技事件

Science & Technology Review. 2010, 28 (14): 11-11. ;  doi:
Full text: HTML (0 KB)  PDF  (328 KB)  ( 180 )
Abstract ( 350 )
科技评论

Science & Technology Review. 2010, 28 (14): 12-12. ;  doi:
Full text: HTML (0 KB)  PDF  (223 KB)  ( 133 )
Abstract ( 311 )

Science & Technology Review. 2010, 28 (14): 122-122. ;  doi:
Full text: HTML (0 KB)  PDF  (259 KB)  ( 178 )
Abstract ( 325 )

Science & Technology Review. 2010, 28 (14): 123-123. ;  doi:
Full text: HTML (0 KB)  PDF  (376 KB)  ( 157 )
Abstract ( 344 )

Science & Technology Review. 2010, 28 (14): 124-124. ;  doi:
Full text: HTML (0 KB)  PDF  (159 KB)  ( 197 )
Abstract ( 309 )

Science & Technology Review. 2010, 28 (14): 125-125. ;  doi:
Full text: HTML (0 KB)  PDF  (621 KB)  ( 194 )
Abstract ( 315 )

Science & Technology Review. 2010, 28 (14): 126-126. ;  doi:
Full text: HTML (0 KB)  PDF  (5952 KB)  ( 271 )
Abstract ( 317 )
科技工作者建议

Science & Technology Review. 2010, 28 (14): 13-13. ;  doi:
Full text: HTML (0 KB)  PDF  (85 KB)  ( 161 )
Abstract ( 348 )
Articles

Deactivation of RbNO3-KF/C in the Pentafluoroethyl Iodide Reaction

Science & Technology Review. 2010, 28 (14): 21-25. ;  doi:
Full text: HTML (0 KB)  PDF  (889 KB)  ( 292 )
Abstract ( 574 )
Pentafluoroethyl iodide(C2F5I) is not only used as the telogens for the telomerization of tetrafluoroethylene to long-chain perfluoroalkyl iodides, but also used as the raw material of intermediate for medicines and agrochemicals. Currently a continuous vapor-phase process for the synthesis of C2F5I has been developed successfully by reacting C2HF5 with I2 in the presence of an alkali or alkaline erath salt supported in activated carbon as catalyst which makes the green production become possible. In this paper, the synthesis of C2F5I via the new novel method was catalyzed by the RbNO3-KF/C catalysts prepared by the equivalent-volume impregnation method. The results indicate that the activity of RbNO3-KF/C catalysts varies continuously with time. By means of BET-BJH, TG-DTA, SEM, XRD, ICP, the deactivation of RbNO3-KF/C catalysts for synthesis of pentfluoroethyl iodide was characterized and compared with the fresh RbNO3-KF/C catalyst. The results indicate that the real active components are RbO and RbF of RbNO3, and the deactivation of the catalytic active component RbNO3-KF/C is mainly caused by the coke-formation on the catalysts during the reaction, and the loss of active components due to the imbalance between carbon deposition and carbon baking.

Screening of Quantitative Diagnosis Indices of Typing Abnormal Hilit Syndrome in Uighur Medicine Using Delphi Method in the Survey of430 Cases of Hypertension

Science & Technology Review. 2010, 28 (14): 33-39. ;  doi:
Full text: HTML (0 KB)  PDF  (1644 KB)  ( 320 )
Abstract ( 548 )
To set up abnormal Hilit typing quantization diagnostic criteria of Uighur medicine for the hypertension patients, according to the free disease clinical diagnostic information, 430 hypertension patients were selected in the study of quantifying diagnosis specialist counseling. Some selected factors were analyzed by a modified multi-categorization logistic regression analysis to determine the contribution degrees of the symptom-complex factors to the main symptoms and subsidiary symptoms of abnormal Hilit of hypertension from the OR values. As a result, the meaningful symptoms are found in all abnormal Hilit syndromes according to the OR values. The features of the four abnormal Hilit syndromes are complicated. The symptom quantitative diagnosis of the abnormal Hilit syndromes provides an objective evidence for clinical practice.

Screening of CoQ10 Highly Productive Mutant Strains by Spaceflight Mutation

Science & Technology Review. 2010, 28 (14): 40-43. ;  doi:
Full text: HTML (0 KB)  PDF  (460 KB)  ( 309 )
Abstract ( 437 )
Spaceflight mutation was carried out to improve Coenzyme Q10(CoQ10) yield to be utilized in industrial microbial fermentation. CoQ10 high yield mutants were screened from Rhodobacter sphaeroides that was collected from a recoverable satellite after a 15-day flight in space. High yield mutant strains were selected based on colony morphology, including colony size and color, and then screened using the method of shake flask fermentation. The CoQ10 production was measured using HPLC. The CoQ10 production of the mutant strain named
"Shenzhou 6" reached (0.8+0.02)g/L, 33% higher than the control group. The production could be increased with the optimization of fementation conditions and the strain could be utilized in the industrial microbial fermentation. Meanwhile, the result revealed that spaceflight showed multi-factor mutagenic effect on Rhodobacter sphaeroides compared to the traditional single-factor mutagenesis methods. It could increased CoQ10 production of isolated strains, and could be utilized in industrial microbial mutagenesis and breeding in the future.

Numerical Simulation of Bubble Behavior in the Liquid Lithium Lead Bubbler

Science & Technology Review. 2010, 28 (14): 44-48. ;  doi:
Full text: HTML (0 KB)  PDF  (1303 KB)  ( 309 )
Abstract ( 458 )
The tritium fuel cycle of the liquid metal blanket is a core technology for the normal operation of a fusion reactor or a fusion-fission hybrid reactor. The tritium fuel circulation system consists of the tritium purification, the tritium extraction, the tritium storage, the tritium measurement, the helium/water cooling and the tritium recovery subsystem. The liquid metal bubbler located between the blanket main circuit and the tritium extraction system is an indispensable key component for its important functions in tritium monitoring and removal. However, the development of a bubbler is difficult as the solubility of hydrogen isotopes in liquid lithium lead is very low and the liquid alloy has some unique characteristics in high temperature, with respect to an effective design and building of Liquid Lithium Lead Bubbler (LLLB) for the Tritium Breeding Module (TBM) of fusion reactor. An algebraic model to describe the gas holdup characterization,
the bubbler diameter and the size distribution is developed under the assumptions that the gas phase is non-Newtonian and there is no frictional force between gas and liquid phases. Simulation results show that bubbles would break up much faster than while being coalesced under low gas velocity. In LLLB, the breakage is a dominant feature for bubbles after they leave the orifice. Initial bubbles formed over the orifice are mostly larger than the largest stable bubble. They would break up quickly and their sizes are reduced to below the maximum diameter ds of stable bubbles. Moreover, the gas-liquid surface area would be increased even though the gas holdup does not change significantly. A high mass transfer area could be obtained by injecting more small initial bubbles with diameters under ds.

Numerical Computation and Flowfield Analysis of Hypersonic Flow overa Double-Cone Body

Science & Technology Review. 2010, 28 (14): 49-55. ;  doi:
Full text: HTML (0 KB)  PDF  (2151 KB)  ( 264 )
Abstract ( 534 )
In recent years, numerous studies about shock/boundary layers and shock/shock interactions in hypersonic flow over a double-cone body were reported. The interaction between a shock wave and a separation zone in a hypersonic flow is a very challenging problem because of its complexity. Previous researches show that the heat transfer rate on the cone forebody is over-predicted by about 20% and the separation zone is slightly too large. The hypersonic flow over 25°~55° sharp double-cones and the blunt double-cone models are simulated by using the Navier-Stokes equations in the conservation integral form with multi-species and non-equilibrium molecular thermal excitation and chemical reactions. The cases presented in this paper include 5 different Mach numbers, which are 15.56, 10.34, 9.59, 8.20 and 8.06, respectively. The surface pressure and the heat transfer rate are obtained, with a good agreement between the continuum CFD simulations and experiments. A preliminary analysis of the effects of the numerical schemes on the simulation of the flow is also presented. It is shown that the simulation results, especially, the size of the separation zone, are very sensitive to the limiter used. The more dissipative limiters tend to reduce the separation zone size. The Roe scheme with van Leer limiter gives the most satisfactory results. The simulation of double-cone flows at high enthalpy in the environment of pure oxygen is also presented.

Application of Equivalent Fracture Flow Model for Productivity Prediction in Natural Fractured Reservoir

Science & Technology Review. 2010, 28 (14): 56-58. ;  doi:
Full text: HTML (0 KB)  PDF  (464 KB)  ( 367 )
Abstract ( 451 )
In order to investigate the productivity characteristics of low permeability reservoirs with natural fractures, the system of natural fractures was simplified and the equivalent fracture flow model was established based on the continuous medium theory. By using the equivalent permeability model, the steady-state productivity equation was set up in naturally fractured low-permeability reservoirs. The productivity equation was applied to an example calculation and the results were compared with the actual production data, to validate the model. The influences of fracture characterization parameters on productivity were analyzed by using the model. These fracture parameters include the fracture width, the fracture length and the fracture permeability. The results show that the fracture permeability has a more important effect on the productivity of naturally fracture low-permeability reservoirs. An important conclusion for better production response is as follows: when the fracture permeability and the fracture width reach a certain level, the longer the length of fracture is, the higher productivity could be obtained.

Study on Sedimentary Facies of the Quaternary in Sanhu Area of Qaidam Basin

Science & Technology Review. 2010, 28 (14): 59-66. ;  doi:
Full text: HTML (0 KB)  PDF  (3962 KB)  ( 319 )
Abstract ( 578 )
The Quaternary of the Sanhu area in Qaidam Basin is subdivided into 5 sequences from bottom to top. The comprehensive analysis of outcrop, core, drilling, logging, seismic and analysis testing data indicates that in the area are developed the facies types such as alluvial fan, fan delta, delta and lake facies, with the lake facies being predominant. The alluvial fan can be subdivided into three subfacies as root, middle part and extremity. The front is predominant in the fan delta and the delta. The lake facies can be subdivided into three subfacies as the shore lake, shallow lake and half-deep lake. In different sequence periods there are different scales of facies. Various facies distribute regularly in space. The alluvial fan and the fan delta facies develop in the southern slope and northern Yaba'er and Quanji areas. The delta facies develop in Yanhu and Qarhan areas. And other areas are all occupied by the lake facies. Each plane distribution of sedimentary facies in each sequence indicates that the depositional places of the half-deep lake and the depositional center have the migration trend from west to east. Finally, on the basis of the comprehensive analysis on various results, the sedimentary model in the studied area is built. And it is pointed that the favorable exploration regions in the studied area are located in Senan-Jinda area and the structure development zones in the northern slope such as Tuoxi, Taidong and Sedong uplifts.

Tripling Construction for Large Sets of Directed Triple Systems with Index 3

Science & Technology Review. 2010, 28 (14): 67-69. ;  doi:
Full text: HTML (0 KB)  PDF  (318 KB)  ( 217 )
Abstract ( 464 )
There are two kinds of oriented triples on X: the cyclic triple and the transitive triple. A cyclic triple on X is a set of three ordered pairs (x, y), (y, z) and (z, x) of X, which is denoted by <x, y, z> (or <y, z, x>, or <z, x, y>), and a transitive triple on X is a set of three ordered pairs (x, y), (y, z) and (x, z) of X, which is denoted by (x, y, z). An oriented triple system of order v with index λ is a pair (X, B)where X is a v-set and B is a collection of oriented triples on X, called blocks, such that every ordered pair of X belongs to exactly λ blocks of B. If B consists of transitive (or cyclic) triples only, the system is called a directed triple system (or Mendelsohn triple system) of order v with index λ and denoted by DTS(v, λ) (or MTS(v, λ)). If B contains both cyclic triples and transitive triples, the system is called a hybrid triple system of order v with index λ and denoted by HTS(v, λ). A triple system is called simple if there are no repeated blocks in B. A simple DTS(v, λ) is called pure and denoted by PDTS(v, λ) if (x, y, z)∈B implies (z, y, x), (z, x, y), (y, x, z), (y, z, x), (x, z, y)?埸B. A large set of disjoint PDTS(v, λ)s, denoted by LPDTS(v, λ), is a collection of {(X,Bi)}i where each (X,Bi) is a PDTS(v, λ) and ∪iBi is a partition of all transitive triples on X. In this paper, a tripling construction for LPDTS(v, 3) is presented, and one infinite family for the existence of LPDTS(v, 3) is obtained: for any positive integers v, v≡8,14(mod18), there exists an LPDTS(v, 3).

Spin-polarized Transport of Electrons Tunneling Through a Double-barrier Magnetic Tunneling Junction

Science & Technology Review. 2010, 28 (14): 70-74.
Full text: HTML (0 KB)  PDF  (882 KB)  ( 332 )
Abstract ( 305 )
Using the coherent quantum transport theory and transfer matrix method, we investigate the spin-dependent transmission coefficient and spin polarization of electrons tunneling through double barriers (DB) sandwiched between two ferromagnets (F). The results indicate that the transmission coefficient and spin polarization oscillate periodically with the increasing of the well width, and the period of oscillation is independent of the barriers thickness. The oscillation frequencies of the transmission coefficient and spin polarization increase with the increasing of the Rashba spin-orbit coupling strength. The amplitude and peak-to-valley ratio of the transmission coefficient and spin polarization are strongly dependent on the relative orientation of the two magnetizations in the left and right ferromagnets. In additional, compared to the ferromagnet/semiconductor/ferromagnet (F/S/F) magnetic tunneling junction, the peak-to-valley ratio of the transmission coefficient and spin polarization increase with the increasing of the barrier thickness, the large spin polarization value can be obtained, and the spin splitting and spin-flipping properties can be observed.

Optimization and Matching of Mini Passenger Car Suspension Parameters Based on Design of Experiment

Science & Technology Review. 2010, 28 (14): 75-79. ;  doi:
Full text: HTML (0 KB)  PDF  (645 KB)  ( 190 )
Abstract ( 484 )
The suspension is a complex mechanical system, for which it is very difficult to define the optimization function. There are more than one system performance indices for every component of the vehicle, which are interrelated, with complicated impact on the vehicle. From a theoretical viewpoint, the objective function to optimize the suspension system is very difficult to formulate. In this paper, based on the multi-body system dynamics method, the virtual prototyping model of a mini passenger car is built. Considering vehicle handling stability and ride comfort, by using the degree of understeering and the roll rate in the steady circular test and the total RMS acceleration values in the method of random input running test of automotive ride comfort as the evaluation indices, the orthogonal experiment is designed, and the effects of the suspension structure parameters on handling stability and riding such as the suspension rate of the front suspension and the rear suspension, the torsion stiffness of the antiroll bar, the damping ratio of the front and rear suspensions are studied. Then the important factors are found, together with the optimum combination of the simulation-based suspension parameters. The final results provide some guidance and support for the optimization of the suspension parameters.

Simulation on walking control system of linear move irrigation

Science & Technology Review. 2010, 28 (14): 80-84. ;  doi:
Full text: HTML (0 KB)  PDF  (825 KB)  ( 351 )
Abstract ( 1359 )
A large scale linear-moving irrigation system is more efficient with less water, but the traditional trial and error involves much waste of water, material and human resource. To avoid this problem, the virtual reality technology is used to simulate the control and drive system. Three-dimensional models of the irrigation system are built according to their scale with Pro/Engineer, and three-dimensional scenes of farmland are established with Multigen Creator software. The mechanical model of the irrigation system is built according to the principles of ground vehicle dynamics. Visual C++ 6.0 and Multigen Vega are used to program an application, which loads the three-dimensional models of the irrigation system into the scenes of farmland. Then the control system and the drive system are simulated to monitor in real-time and to optimize the system parameters. The simulation results and tests show that the system can reflect the large-scale irrigation effectively, and optimize the control parameters through simulation, with the error of angle less than 0.04°.

Efficiency of Sift Image Matching Algorithm of Different Dimensions

Science & Technology Review. 2010, 28 (14): 85-89. ;  doi:
Full text: HTML (0 KB)  PDF  (1129 KB)  ( 246 )
Abstract ( 1311 )
For mobile robot visual positioning, SIFT (Scale Invariant Feature Transform) algorithm is widely used because of its features of scale, rotation and illumination invariability. The efficiency of the SIFT image matching algorithm is related to the number of dimensions, which is taken as the characteristic point to meet different image matching precision and real-time requirements. To solve this problem, for different dimensions of the SIFT algorithm, experimental analysis was carried out for efficient matching to obtain a range of dimensions with a certain degree of practical significance. The test results show that, for image position, the characteristic point dimension functions are different. For a high performance of real-time image positioning, the function of 1×1×N is selected, and for the mobile robot image positioning, a high real-time but normal position precision is needed, the function of 2×2×N is a best choice. Taking the robot navigation of visual indoor positioning as an example, selecting 16 dimensions in a dimension matching of experimental results of the mobile robot, the needs of real-time location can be satisfied.

Preparation and Properties of Starch-Kaolin/P(AA-AM) Super Absorbent Resin

Science & Technology Review. 2010, 28 (14): 90-94. ;  doi:
Full text: HTML (0 KB)  PDF  (965 KB)  ( 332 )
Abstract ( 441 )
The superabsorbent is one of the fastest developing functional polymers. The USA, Europe and Japan are the main producers and consumers. China's research in this field started later, but with a good progress. Compared with the mainstream product preparation from acrylic acid, that by using starch as raw material has many advantages, for starch is abundant, cheap and biodegradable. This paper studies its preparation process, morphology and structural characterization. The influencing factors on absorbency include the components of kaolin, the type and amount of initiator, the type and amount of crosslink, amount of acrylamide, neutralization degree, and drying conditions. With acrylic acid, acrylamide, kaolin, starch and others as raw materials, super-absorbent composites were prepared by using a method of water solution cross-linked polymerization The aqueous solution polymerization method is discussed, focusing on the properties of super absorbent resin, which are affected by the amount of crosslinking agent, initiator, kaolin, acrylamide and drying condition, and so on. Water absorption rate can reach 1415g/g, and salt absorption rate can reach 95g/g. The copolymers were characterized by the IR spectroscopy and Scanning Electronic Microscopy (SEM). A good thermal stability is shown, and the components of comonomers influence the resin's decomposition temperature and the surface morphological characterization notably.

Spatial Equilibrium of Inter-provincial Ecological Pressure in China

Science & Technology Review. 2010, 28 (14): 95-97. ;  doi:
Full text: HTML (0 KB)  PDF  (658 KB)  ( 179 )
Abstract ( 464 )
There is an imbalance between the ecological pressure and its carrying capacity. One should understand the relationship between people and land to evaluate quantitatively the imbalance and analyze its evolution. Based on the calculation of ecological pressures and its carrying capacity, this paper analyzes China's spatial equilibrium of the ecological pressure and its influence factors by use of the ecological Gini coefficient and the spatial equilibrium index. The results show that China's ecological Gini coefficient is 0.2771 and 0.3779 in 2000 and 2008. The ecological pressure space is relatively balanced, but the imbalance between the ecological pressures and its carrying capacity has been expanded. More central and western provinces belong to "harmonious man-land pattern" and the spatial non-equilibrium factors are mostly contributed by the eastern provinces. The regional difference of the relative relationship between the ecological pressure and the carrying capacity leads to the regional difference of the man-land relationship. In order to coordinate the relationship between human and land in China, it is an important for the regional ecological economic policy to be based on the spatial equilibrium of the ecological pressure.

Atmosphere Thermal Anomaly Before Zhangbei Earthquake in 1998

Science & Technology Review. 2010, 28 (14): 98-100. ;  doi:
Full text: HTML (0 KB)  PDF  (757 KB)  ( 247 )
Abstract ( 500 )
The thermal anomaly before earthquake was widely studied during the last 20 years; in most cases the thermal anomaly is far away from the epicenter, so it is difficult to predict the epicenter with this anomaly. In this paper, the air temperature data was used to study the thermal anomaly before the Zhangbei earthquake of Jan. 10, 1998. The results show that an isolated area with high temperature appeared at a place close to the epicenter 13 days before this quake, at the same time the temperature was also the maximum value in the whole east China. The long axis of this area points northeast, the same as that of Shangyi-Duolun fault. The air temperature along the northwest Zhangbei-Bohai fault reached the maximum value at Zhangbei station one day before the quake, and the Ms 6.2 quake occurred at the intersection area of these two fault systems. If the center of the thermal anomaly area was predicted as the future epicenter, the error will be 80km, as a much better result than most other predictions. It shows that the meteorology data are also useful in earthquake predictions. At the same time, the meteorology data can be obtained and processed with a national uniform criterion, and are easily available to researchers. The subtraction method considers the relative temperature change, which may eliminate the influence of the temperature difference caused by different local climates. If the geophysical data measured by seismic stations are combined with the meteorology data, a better earthquake prediction would be possible.

Salicylaldehyde-modified Chitosan's Property of Adsorption to Chlorophenols Compounds

Science & Technology Review. 2010, 28 (14): 101-104. ;  doi:
Full text: HTML (0 KB)  PDF  (1831 KB)  ( 221 )
Abstract ( 478 )
Waste water with phenol is very harmful to the health of human beings. In order to effectively solve the serious problem of 2,4-dichlorophenol's pollution to water resources, the salicylaldehyde-modified chitosan's synthesis and its property of adsorption to 2,4-dichlorophenol are studied. A comparison of the adsorption ability between the modified chitosan and the un-modified chitosan is made. The synthesis method of salicylaldehyde-modified chitosan is discussed. The structure of the modified chitosan is characterized by FT-IR. The adsorption of 2,4-dichlorophenol by the modified chitosan is investigated by the UV spectrum method. The effects of pH value, time and concentration of phenol on adsorption property are analyzed. It is shown that the modified chitosan has better adsorption property than the un-modified chitosan. The adsorption ability is improved from 26.8mg/g of the un-modified chitosan to 38.7mg/g of the modified chitosan. The modified chitosan has the best adsorption effect when the adsorption time is above 2h and pH value of the solution is 5. With the increase of the concentration of phenol, the adsorption capacity is increased near linearly. After 50 minutes, the adsorption capacity of the modified chitosan approaches almost saturation. When the mass of the modified chitosan is above 0.5g, the adsorption capacity reaches the maximum. The adsorption property fits well with the Langmuir isotherm adsorption equation. The adsorption kinetics fits well with the second-order dynamic model.
Reviews

A Review of Influenza Vaccine Researches

Science & Technology Review. 2010, 28 (14): 105-108. ;  doi:
Full text: HTML (0 KB)  PDF  (301 KB)  ( 244 )
Abstract ( 442 )
Pandemic influenza poses a grave threat to all mankind. Vaccination is widely considered to be the first line of defense for protecting populations in advance against an influenza pandemic, so the adequate and timely supply of effective vaccines is an urgent issue for the preparedness against the pandemic. There are a number of problems that concern the vaccine uses today, for example,
(1) the production cycle is too long to respond to a novel virus; (2) because it is not known beforehand which strain of influenza virus would give rise to a pandemic, vaccines that impart broad cross-reactive immunogenicity are required, but the cross-protection of vaccines between different strains are very weak; (3) many people are allergic to the vaccines because of something in the egg medium. In order to be prepared for the pandemic influenza that may occur in a future time, a concerted effort from public health, commercial and scientific sectors is required. In this paper, the advantages and disadvantages of the inactivated influenza vaccines and the attenuated live influenza vaccines are discussed. Some aspects related with tackling the obstacles facing the development of influenza vaccine, e.g. the protecting period and the proper medium, and research progresses achieved are reviewed, including some key scientific issues in basic research of influenza, such as virus transmission, host restriction and pathogenesis, which are very important to the influenza vaccine development and pandemic control. Research progresses of influenza in China are also discussed. Some suggestions for influenza control and prevention are proposed.

A Review of Prediction Methods for Reservoirs of Tight Factured Clastic Rock

Science & Technology Review. 2010, 28 (14): 109-112. ;  doi:
Full text: HTML (0 KB)  PDF  (272 KB)  ( 222 )
Abstract ( 406 )
Engineering practice shows that reserves of tight fractured reservoirs of clastic rock account for a large proportion of the total reserves of low permeability reservoirs. Their researches are important for exploration and development of oil and gas. An important difficulty in exploration and development of tight fractured reservoirs of clastic rock is how to accurately predict the growth degree and distribution range of reservoir fractures. In this paper, the methods of fracture prediction for tight reservoirs of clastic rock are systematically reviewed, including geological analysis, curvature method and tectonic stress simulation, seismic fracture identification technique, log fracture identification technique and production performance analysis. It is pointed out that there are two development trends for macroscopic fracture predictions of tight reservoirs of clastic rock: the innovation in the single methods of fracture prediction and the systematical engineering method integrating advantages of different single methods for fracture prediction.

History, Present State and Future of Non-destructive Testing for Wood

Science & Technology Review. 2010, 28 (14): 113-117. ;  doi:
Full text: HTML (0 KB)  PDF  (344 KB)  ( 310 )
Abstract ( 468 )
The Non-Destructive Testing (NDT), that does not damage the tested object and influence its performance, is an effective method, where various physical principles and chemical phenomena are involved. Its advantages include short measuring time, simple method, high stability, no destruction and capability of working in continuous production. It has been widely used in the field of wood science and engineering. In this paper, the mechanical properties of wood are studied by non-destructive testing and the wood is graded by wood strength. Different non-destructive testing methods are compared in the tests of mechanical properties, and their importance is shown in wood utilization, production costs and production efficiency. An review of the history, the present state, and the future development of NDT is given.

Science & Technology Review. 2010, 28 (14): 118-118. ;  doi:
Full text: HTML (0 KB)  PDF  (59 KB)  ( 225 )
Abstract ( 335 )
Focus

Science & Technology Review. 2010, 28 (14): 120-121. ;  doi:
Full text: HTML (0 KB)  PDF  (97 KB)  ( 142 )
Abstract ( 337 )
主编心语

Science & Technology Review. 2010, 28 (14): 127-127. ;  doi:
Full text: HTML (0 KB)  PDF  (924 KB)  ( 234 )
Abstract ( 301 )
走向职场

Science & Technology Review. 2010, 28 (14): 128-128. ;  doi:
Full text: HTML (0 KB)  PDF  (448 KB)  ( 269 )
Abstract ( 327 )

Science & Technology Review. 2010, 28 (14): 129-129. ;  doi:
Full text: HTML (0 KB)  PDF  (203 KB)  ( 267 )
Abstract ( 324 )

Science & Technology Review. 2010, 28 (14): 130-134. ;  doi:
Full text: HTML (0 KB)  PDF  (445 KB)  ( 135 )
Abstract ( 327 )

Science & Technology Review. 2010, 28 (14): 135-139. ;  doi:
Full text: HTML (0 KB)  PDF  (985 KB)  ( 183 )
Abstract ( 313 )

Copyright © Editorial office of Science & Technology Review
Tel: +86-10-62138113 Fax: +86-10-62138113 E-mail: jdbbjb@cast.org.cn
京ICP备14028469号-1