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   Science & Technology Review
2010, Vol.28, No. 21
13 November 2010

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Reviews
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卷首语

Science as a Whole and Scientific Methodology

Science & Technology Review. 2010, 28 (21): 3-3. ;  doi:
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Abstract ( 419 )
特别栏目

Science & Technology Review. 2010, 28 (21): 8-8. ;  doi:
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Abstract ( 333 )

Science & Technology Review. 2010, 28 (21): 10-10. ;  doi:
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Abstract ( 416 )

Science & Technology Review. 2010, 28 (21): 14-15. ;  doi:
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Abstract ( 367 )

Science & Technology Review. 2010, 28 (21): 16-17. ;  doi:
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Abstract ( 329 )

Science & Technology Review. 2010, 28 (21): 18-19. ;  doi:
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Abstract ( 401 )

Science & Technology Review. 2010, 28 (21): 20-20. ;  doi:
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Abstract ( 375 )

Science & Technology Review. 2010, 28 (21): 127-127. ;  doi:
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Abstract ( 422 )

Science & Technology Review. 2010, 28 (21): 140-140. ;  doi:
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Abstract ( 380 )
封面图片说明

Science & Technology Review. 2010, 28 (21): 8-8. ;  doi:
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Abstract ( 399 )
半月科技风云

Science & Technology Review. 2010, 28 (21): 9-9. ;  doi:
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Abstract ( 501 )
科技事件

Science & Technology Review. 2010, 28 (21): 11-11. ;  doi:
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Abstract ( 425 )
科技评论

Science & Technology Review. 2010, 28 (21): 12-12. ;  doi:
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Abstract ( 367 )

Science & Technology Review. 2010, 28 (21): 122-122. ;  doi:
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Abstract ( 380 )

Science & Technology Review. 2010, 28 (21): 123-123. ;  doi:
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Abstract ( 396 )

Science & Technology Review. 2010, 28 (21): 124-124. ;  doi:
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Abstract ( 383 )

Science & Technology Review. 2010, 28 (21): 125-125. ;  doi:
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Abstract ( 387 )
科技工作者建议

Science & Technology Review. 2010, 28 (21): 13-13. ;  doi:
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Abstract ( 429 )
Articles

Frame Design of a Visual Simulation and Co-design System for Sounding Rockets Based on High Level Architecture

Science & Technology Review. 2010, 28 (21): 21-25. ;  doi:
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Abstract ( 476 )
The sounding rocket is the only method for near space field detection and a good carrier for various space scientific experiments. Currently, the sounding rocket is widely used in middle and upper atmosphere stereo profile detection, microgravity scientific experiment, space biology, spaceborne payload verification test and others, where the sounding rocket shows irreplaceable advantages and functions. Developing the sounding rocket technology and building up a simulation system for sounding rockets will help the construction of the Sounding Rockets Comprehensive Experiment Platform and promote the development of space science in China. With a high flight speed and a short flight time, it is difficult to observe the attitude change during the flying of a sounding rocket. The visual simulation for the sounding rocket can solve this problem. So far, the visual simulations are limited to some simple visual simulations and applications. This paper proposes a distributed visual simulation frame for sounding rockets, based on High Level Architecture (HLA), and a distributed co-design. According to the requirements of building a visual simulation and co-design system for sounding rockets (VSCSSR), some related technologies are introduced, such as visual simulation, distributed interactive simulation and HLA. The main functions, the software and hardware architecture of the system, and the partition of federates are included in the frame design of the system.

Effect of Doped-CeO2 on the Structure and the Ultra-Violet Absorption Property of ZnO Thin Film

Science & Technology Review. 2010, 28 (21): 26-29. ;  doi:
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Abstract ( 544 )
ZnO thin film is a compound semiconductive material of hexagonal Wurtzite structure with a wide application in many areas such as transitive conductive window materials, ultraviolet detectors, LEDs and LDs luminance devices due to its unique electrical and optical properties, good chemical stability, high active energy and melting point, abundance, cheap and nontoxic source, and relatively low preparation temperature. Recent researches show that the properties of ZnO thin film are greatly changed while being doped with some elements. In our experiment, high quality ZnO thin films doped with CeO2 were prepared by RF magnetron sputtering technique. The influence of CeO2 on the structure and optic absorption property was studied by XRD apparatus and UV-visible spectrophotometer. The results show that the CeO2- doped films have a prominent effect on the developing ways of crystal grains and UV absorption property. The lattice relaxation and the content of second phase increase when more Ce is doped. ZnO crysal grains grow in mixing directions. The element Ce exists in many forms in the film. The film's UVA absorption is enhanced. The ultraviolet absorption peak becomes wider and the absorption intensity increases. The slope of the absorption margin is increased and the absorption edge obviously moves to short wave direction when more Ce is doped. In addition, the breadth of the absorption peak is increased and the absorption intensity improved. The visible absorption increases in some extent.

DFH Control Components Built Head over the Reliability of Load and Head Temperature Experiment Design

Science & Technology Review. 2010, 28 (21): 30-33. ;  doi:
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Abstract ( 492 )
Combined with Aatomic Force Microscope (AFM) testing methods, from the size and property of the deformation to assess the head of the built-in Dynamic Flight Height (DFH) components. The results show that, even in a long time over-current circumstances, the processes of the built-in DFH components still belong to the nature of elastic deformation, no permanent plastic deformation occurs. In the still air cooling conditions, AFM results show that the relationship of the size of the distortion and energy about the head of the built-in DFH components is linear. Using the Destructive testing methods of pulsed electric field, the voltage breakdown test to the built-in DFH components was carried out, and the tests shows that the breakdown voltage of the actual product is outside the security zone. Meanwhile, the result demonstrates that the method of adding cooled paste to the static disc surface is possible. Thus it would further simplify the experimental process of the head temperature rise.

OFDM-IJF-OQPSK Modulation Scheme

Science & Technology Review. 2010, 28 (21): 34-36. ;  doi:
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Abstract ( 482 )
Orthogonal Frequency Division Multiplexing (OFDM) suffers from high out-of-band radiation. In this paper, an OFDM-IJF-OQPSK modulation scheme is proposed. Every subcarrier of this scheme is modulated with Intersymbol Interference and Jitter Free-Offset Quadrature Phase Shift Keying (IJF-OQPSK), instead of Multi-level Phase Shift Keying (MPSK) or Multi-level Quadrature Amplitude Modulation (MQAM). On the basis of analyzing OFDM and IJF-OQPSK principle, OFDM-IJF-OQPSK modulation scheme is presented firstly, and then its Power Spectrum Density (PSD) is derived. It is shown that the final PSD is the summation of all the IJF-OQPSK baseband PSDs at all subcarriers of OFDM. Finally, the performance is analyzed by computer simulation and the results show that the out-of-band radiation of this modulation scheme can be reduced significantly.

Diagenesis of Sandstone Reservoirs in Jingbian Gas Field, Ordos Basin

Science & Technology Review. 2010, 28 (21): 37-42. ;  doi:
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Abstract ( 609 )
The low porosity and low permeablity of Permian sandstone reservoirs are the key puzzling issues in gas exploitation in Jingbian gas field, Ordos basin. To analyze the poor property of sandstone reservoirs and improve the accuracy of reservoir forecast, the diagenesis and its controls on reservoir property of sandstone in this area are studied by using systematic slice identification, mercury penetration,cathodoluminescence and scanning electron microscope. It is shown that lithology of P2h8 sandstone in Jingbian gas field is dominated by lithic sandstone, lithic silicarenite and silicarenite with carbonate, gaolinite, chlorite and siliceous cementation. Content of carbonate cementation influences greatly the properties of reservoirs. Reservoir space is domanited by secondary porosity, including the remaining primary intergranular pores, intergranular dissolution pores, intergranular corrosion expanding pores, intragranular dissolved pores, intergranular pores in Kaolinite, and some micro-cracks. Sandstone reservoirs in P2h8 consist mainly of rocks of type II and type III with small portion of rocks of type I. The sedimentary microfacies and the diagenesis controlled development of reseroirs are considered as the main material basis of reservoirs. Well diagenesis alteration is the key factor that determines properties of reservoirs. Compaction and cementation are the main controls on degrading physical properties of reservoirs. Extensively developed dissolvement of aluminosilicate minerals plays a key role in improving properties of reservoirs.

Volcanic Characteristics and Eruption Models of Yingcheng Formation No. 1 Member in Gulong Fault-Depression of Songliao Basin

Science & Technology Review. 2010, 28 (21): 43-47. ;  doi:
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Abstract ( 502 )
The volcanic characteristics and eruption models of Yingcheng Formation No.1 Member in Gulong Fault-Depression of Songliao Basin are studied based on the data and technologies of drilling, logging and seismic conditions. It is shown that four kinds of volcanic rocks, the volcanic lava, the volcaniclastic lava, the volcaniclastic rock, and the sed volcanic pyroclastic rock, were found in the studied area, with the development of mainly three kinds of volcanic facies: the explosive facies, the effusive facies and the volcanogenic sedimentary facies. On the plane, the explosive volcanic facies are mainly distributed at the north of the studied area, with a string of beads along the faults of every level, which control the fault-depression; the effusive volcanic facies are migrated towards the downstructure location along the faults, distributed largely at the studied area; and the volcanogenic sedimentary facies are mainly distributed at the downstructure location of the studied area. In view of the above facts, a crack- central vent eruption model is proposed, which assumes volcanic eruption at the every level of faults which controls the fault-depression, and which would provide some guidance for the further exploration of volcanic activities in the studied area.

Dynamic Bayesian Models for Gob Roof Accidents

Science & Technology Review. 2010, 28 (21): 48-51. ;  doi:
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Abstract ( 491 )
The roof damage is one of the major cause of hazards in the gob in case of collapse accidents. In the stability analysis of the mined area on the roof with multi-objective evaluation and decision analysis, the extensive use is made of analytic hierarchy process, utility function method, and fuzzy membership function method. Among a variety of objectives, a complex relationship often makes the use of these analysis methods very difficult, especially in determining the weight factors of the objectives, which would affect the application of these methods. In the context of the gob roof accident and the Fault Tree Analysis (FTA), the qualitative analysis based on Bayesian network is transformed by the method of the gob roof fault tree transformation, to establish the gob roof accident Bayesian network model, with the use of packages based on Matlab BNT quantitative calculation, In this way, it is necessary to determine weights and the prior probability and the posterior probability are used in comparison and analysis of the gob to identify the main factors related to the gob roof accidents in the conditional probability, with the construction workers not working in accordance with the design and improper exploitation and support being of the greatest importance, therefore, in the actual construction process, the construction workers must strictly follow the design of mining, to enhance support to ensure the stability of the gob roof.

Path Planning for Unmanned Ground Vehicle Based on Map Building

Science & Technology Review. 2010, 28 (21): 52-58. ;  doi:
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Abstract ( 566 )
This paper puts forward a two-layered path planning algorithm to be used for map building and path planning at the same time. The function of the upper layer is to create sub-goals, and the lower layer is to plan local routes. Based on the system real-time demand, the task of creating sub-goals is carried out at intervals of N system cycles. But at every system cycle, the algorithms of planning the local routes and motion controls are all carried on for the safety of system. The map building algorithm makes use of the information acquired by the Unmanned Ground Vehicle (UGV) and the environment information is processed by sonar, which is combined into the local map, to generate and renew grid-occupation based map. Based on the map, the A-star algorithm creates sub-goals and plans the route which makes the assessment function reach a minimum. At every system cycle, the "following-wall" strategy based on fuzzy control is implemented to avoid obstacles due to sub-goals. In this paper, the strategy is divided into the left following-wall and the right following-wall to decide which boundary of the obstacle to follow using the information from sonar synchronously. The algorithm is verified on Pioneer 3-AT UGV in an unknown and complicated environment. It is shown that the system can achieve practical map building and path planning with a good accuracy. The system supported in this paper is easy to extend and re-structure and to be transplanted to other systems.

A Tracing System Based on One-dimensional Electronic Code for Quality Safety of Green Fruits

Science & Technology Review. 2010, 28 (21): 59-62. ;  doi:
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Abstract ( 463 )
This paper discusses quality safety issues for green fruits through tracking records of key information from the orchard cultivation to consumption market of fruits. To ensure the traceability of quality safety for green fruits, the essential indexes of tracing process of fruits are established for the one-dimensional tracing system to meet the requirement of EAN·UCC coding and to save information of planting and distribution of fruits, based on Windows Server 2003 operating system, Microsoft Visual Studio 2008 developing platform and C# programming language. The information labels of orchard, processing distribution and marketing are designed, respectively, for the users to check the origin information of purchased fruits to achieve the traceability for green fruits. The traceability information includes key links such as locality environment, production, processing, distribution and consumption of fruits.

Climatic Zoning of Grapevine in Shandong Province

Science & Technology Review. 2010, 28 (21): 63-67. ;  doi:
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Abstract ( 1353 )
The climatic data of 120 meteorological stations in Shandong Province(provided by China Meteorological Administration) for 30 years (1979—2008) are used in this study, excluding three stations whose data are lost or which are not suitable to plant grapes. Based on the climate data of 120 meteorological stations, Shandong Province can be classified by using the zoning indexes proposed by Lihua et al. with the number of frost free days as the first index, the dryness index (DI, from April to September) as the secondary index and the mean lowest temperature below -15℃ as the tertiary index. The results show that the DI in the growing period (from April to September) is a good index in judging whether an area is suitable for vine cultivation, but is not a good index in estimating how good the area is for vine cultivation. So in this paper, the precipitation in the mature season (from July to September) is chosen as the fourth index. These indices are handled by Excel software and are plotted by ArcGIS software. By applying this zoning system, Shandong Province is divided into 7 cultivated zones, with one that can produce the highest quality grapes, one for high quality grapes, 3 zones for general quality grapes and one zone that can only produce wine. An evaluation on the varieties adopted in every zone is made and it is concluded that Shandong Province is suitable to grow late-harvested or surplus mature grape varieties.

Synthesis of 5-xylose Ester Derivatives and Their Application in Cigarette Flavoring

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Science & Technology Review. 2010, 28 (21): 68-74. ;  doi:
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Abstract ( 649 )
In order to develop new cigarette flavors, a sensory evaluation is made of cigarettes added with sugar esters, synthesised with some volatilizable organic acids with flavors. Taking 1,2-O-propylidene- -D-furan xylose and a series of organic acids with flavors as raw materials, exsiccated sodium carbonate and 4-dimethylaminopyridine (4-DMAP) as catalyst, N,N'-dicyclohexyl carbodiimide (DCC) as condensing agent, through the esterification, 15 kinds of 5-xylose ester derivatives were synthesized in which 13 compounds were new ones. All the structures of the compounds were confirmed by IR, 1H NMR, MS spectra and elemental analysis. The results of tobacco flavoring experiments of these 15 kinds of compounds show that, compared with cigarette control group, adding sugar esters precursor into cigarettes could improve the aroma quality, increase the aroma quantity, harmonize the aroma, clean the after-taste and reduce offensive odor of cigarettes. It is concluded that the synthesised 5-xylose seter derivatives could be used as flavor materials in cigarette flavoring.

Contractible Edges of the Longest Cycle in Some 6-Connected Graphs

Science & Technology Review. 2010, 28 (21): 75-77. ;  doi:
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Abstract ( 522 )
Contractible edges and removable edges in connected graphs are a powerful tool to study the structures of connected graphs and to prove some properties of connected graphs by induction. Let G be a 6-connected graph, an edge of G is called a 6-contractible edge if its contraction remains a 6-connected graph. In this paper, we adopt the method of a tree structure theory and obtain the following results: (1) Let P:x=x1x2…xn=y is the longest road of G, xi xi+1 is an uncontractible edge, and S={xi, xi+1, u1, u2, u3, u4} is the corresponding 6-vertex cut, then there is at least one vertex of P in every fragment of G-S. (2) Let P:x=x1 x2…xn=y is the longest road of G, and any fragment's order is bigger than 2. If any vertex in P satisfies the condition (a) d(xi)≥7 or (b) if d(xi)=6, there is no 3-circle which contains the vertex, there is at least one contractible edge in P. Based on the above results, we consider an arbitrary fragment whose order is greater than 2, and the contractible edge's distribution in the longest cycle of 6-connected graphs and obtains the following result: if arbitrary fragment's order is greater than 2, then there are at least two contractible edges in the longest circle of 6-connected graphs.

On the Equitable Adjacent-Vertex-Distinguishing Total Coloring of Graphs of Some Classes

Science & Technology Review. 2010, 28 (21): 78-81. ;  doi:
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Abstract ( 478 )
With the definition of proper total coloring of a graph, an Adjacent Vertex-Distinguishing Total Coloring (AVDTC) means that none of the two adjacent vertices are incident with the same set of colors. The concept of the AVDTC is proposed by Zhongfu Zhang (2004), and the AVDTC of graphs such as path, cycle, complete graph, complete bipartite graph, star and tree are discussed in Zhang's paper. The AVDTC of Pm×Pn , Pm×Cn , Cn×Cn are also given where Pm , Cn are a denoted path with order m and a circle with order n,
respectively; the AVDTC of Mycielski graph of some graphs such as path, circle and so on are given in another Zhang's paper (2000). For the adjacent vertex-distinguishing total chromatic number, a conjecture is given in Zhang's paper (2004). Let G(V, E) be a simple
connected graph of order n(n≥2), k be a natural number and f be a k-adjacent vertex-distinguishing total coloring of graph G. If f satisfies the condition ||Vi∪Ei|-|Vj∪Ej||≤1 (i≠j), where Vi∪Ei={v|f(‘v)=i}∪{e|f(e)=i}, C(i)=Vi∪Ei, then f is called an equitable
adjacent vertex-distinguishing total coloring of graph G(k-EAVDTC) and χeat(G)=min{k∣G has k-EAVDTC} is called the chromatic
number of the equitable adjacent-distinguishing total coloring of graph G. This paper gives the equitable adjacent vertex distinguishing total coloring chromatic number of path Pn and cycle Cn and graph Kt3 andgraph Dm,4 and gear wheel ■n.

Influencing Factors of the Thermal Environment of Atrium Based on the Orthogonal Analysis Method

Science & Technology Review. 2010, 28 (21): 82-85. ;  doi:
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Abstract ( 454 )
Atrium thermal amenity is determined by many factors, as were investigated widely both at home and abroad. But the relationship and interactions between these factors have not been well studied. In this paper, three thermal environment influencing factors: the cross section area of atrium, the outdoor air temperature and the top skylight opening percentage are orthogonally analyzed. First, the experimentation is designed by using the method of orthogonal analysis. Then numerical simulations are carried out according to different test conditions, and simulation results are orthogonally analyzed. The results indicate that the top skylight opening percentage has the greatest impact on the airflow volume of atrium, the section area of atrium plays a secondary role, and outdoor air temperature is relatively less important. But the outdoor air temperature is an important influencing factor on the temperature distribution in atrium. This analysis provides a scientific basis for the rational engineering design and operation management. Proposals for improving the thermal amenity and energy efficiency for the completed building are also given.
Reviews

Basic Methods to Inverse Exhumation Rates Using Low-Temperature Thermochronological Data

Science & Technology Review. 2010, 28 (21): 86-94. ;  doi:
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Abstract ( 429 )
Low-temperature thermochronology not only is a geochronological tool to date a rock but also can provide valuable information about its thermal evolution. Accordingly, this technique has been widely used to solve the geological problems including surface processes, rock exhumation, or faulting in shallow crust, topographic relief evolution etc. This paper first briefly reviews the principles of low-temperature thermochronometries such as (U-Th)/He and fission track analysis, focusing on its geological interpretations on tectono-thermal history. Then the physical conditions of regional geothermal field and its influences on the interpretation of low-temperature thermochronometers are discussed. The main part of this paper discusses the basic methods to constrain the exhumation rate based on low-temperature thermochronological data, including (1) the age-closure temperature method using the relationship between the cooling age and the closure temperature; (2) the thermal history modeling method based on the annealing or diffusion models; (3) the mineral-pair method dating a same sample by multiple thermochronometers with different closure temperatures; and (4) the age-elevation relationship method extracting exhumation rate by the linear relationship of the ages and elevation data of a series of samples collected from a near-vertical profile. Although the above methods prove to be powerful in estimating the rock exhumation rate, there are some uncertainties in age measurements, modeling and geothermal field, which pose challenges for a more accurate quantification of exhumation rate.

Research Progress on the Therapeutic Dosimetry of High Intensity Focused Ultrasound

Science & Technology Review. 2010, 28 (21): 95-100. ;  doi:
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Abstract ( 483 )
High Intensity Focused Ultrasound (HIFU) is a new type of physical therapy, consistent with the concept from invasive to noninvasive or minimally invasive treatment. The relationship between HIFU dose and biological effects is important and is difficult to determine, but also is one of the keys for the clinical application of HIFU technology. This paper presents a review of HIFU, including the therapy principle, system's basic structure, core technology and characteristics, especially the damages from thermal heat, mechanical and cavitations effect. Based on the assessment of HIFU technology, domestic and international research trends on therapeutic dosimetry are discussed and the key links between the dose-effect relationship and frequency, sound power, radiation time, treatment methods, treatment depth, biological characteristics and acoustic environment of the organization are highlighted. Three major issues are stressed: monitoring system, sound channels and the "double standards" of dose- effect relationship, and proposals are given about developing dose study and HIFU technology. With the development and improvement of HIFU technology, the features of high efficiency, safety, noninvasive, and real-time monitoring will become more prominent, and it will play a more and more important role in the field of medicine.

Epidemiology of Polycystic Ovary Syndrome

Science & Technology Review. 2010, 28 (21): 101-105. ;  doi:
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Abstract ( 554 )
Although Polycystic Ovary Syndrome (PCOS) appears to be one of the most common endocrine disorders of women, it is not well understood by clinical doctors. Several studies both at home and in the United States show that there are significant ethnic and racial variations in the clinical characteristics of PCOS. This paper reviews studies of Polycystic Ovary Syndrome epidemiologic surveys and it is concluded that the PCOS has significantly lower occurrence in China than in the United States. It is suggested that the initial diagnostic criteria of PCOS include: (1) irregular estrous cycle, abnormalities and oligo-ovulation; (2) higher luteinizing hormone;
(3) polycystic ovarian morphology.

Factors Affecting Oxidation and Self-heating of Sulfide Ores in Stope

Science & Technology Review. 2010, 28 (21): 106-111. ;  doi:
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Abstract ( 479 )
The oxidation and self-heating of sulfide ores deposited in stope is a cause of environmental pollution, caking problems of ores, and spontaneous combustion fire in metal mines. The main factors affecting the oxidation and spontaneous heating of sulfide ores are discussed in this paper, including the crystal structure, trace metal content, environmental temperature, oxygen concentration, moisture, particle size, environmental pH value, ferric iron, bacteria, among others. It is shown that the reaction modes of sulfide ores at ambient temperature are complex; the oxidation and self-heating are influenced by many factors; an increase in temperature and oxygen concentration has an increasing effect on the oxidation and self-heating; the reactivity increases as the particle size decreases; both ferric iron and bacteria act as catalysts in the oxidation; water has effects on both the oxidation and self-heating; whereas neither crystal structure nor trace metal content has a consistent effect on the oxidation rate.

Review of Anaerobic Dechlorination of High Concentrated Trichloroethylene in Groundwater

Hai-Zhu HU;
Science & Technology Review. 2010, 28 (21): 112-117. ;  doi:
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Abstract ( 528 )
Trichloroethylene (TCE) is an organic solvent widely used in industry and commonly exists in soil and groundwater, while high concentrated TCE may lead to persistent pollution. Based on the feasibility of the degradation of high concentrated TCE, the pathway of anaerobic reductive dechlorination and the main factors influencing degradation, i.e., electron donor and microorganism, were reviewed in this paper. Meanwhile, we discussed the impact of pH and various restricting factors on the degree and the rate of reductive dechlorination. Commonly used kinetic models for the reductive degradation kinetics were listed and compared. The trend of future research was discussed. In experiment, selecting and cultivating of dechlorination bacterium which can survive in source zones with high concentrated chlorinated ethene and the effect of electron donor substrates need further study. In numerical simulation, models are required for comprehensive simulation of biological reaction, hydrogeochemical reaction, as well as physical flow and multi-species transport in groundwater. Moreover, parameters in these models lack verification, which need further study.

Science & Technology Review. 2010, 28 (21): 118-118. ;  doi:
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Abstract ( 415 )
Focus

Science & Technology Review. 2010, 28 (21): 120-121. ;  doi:
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Abstract ( 621 )

Science & Technology Review. 2010, 28 (21): 126-126. ;  doi:
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Abstract ( 641 )
主编心语

Science & Technology Review. 2010, 28 (21): 127-127. ;  doi:
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Abstract ( 384 )
走向职场

Science & Technology Review. 2010, 28 (21): 128-128. ;  doi:
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Abstract ( 398 )

Science & Technology Review. 2010, 28 (21): 129-129. ;  doi:
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Abstract ( 424 )

Science & Technology Review. 2010, 28 (21): 130-134. ;  doi:
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Abstract ( 378 )

Science & Technology Review. 2010, 28 (21): 135-139. ;  doi:
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Abstract ( 400 )

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