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   Science & Technology Review
2009, Vol.27, No. 0922
28 November 2009

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Reliability and Our Life

Science & Technology Review. 2009, 27 (0922): 1-1. ;  doi:
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特别栏目

Science & Technology Review. 2009, 27 (0922): 8-8. ;  doi:
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Science & Technology Review. 2009, 27 (0922): 10-10. ;  doi:
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Science & Technology Review. 2009, 27 (0922): 12-13. ;  doi:
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Science & Technology Review. 2009, 27 (0922): 14-14. ;  doi:
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Science & Technology Review. 2009, 27 (0922): 15-15. ;  doi:
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Science & Technology Review. 2009, 27 (0922): 16-16. ;  doi:
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Science & Technology Review. 2009, 27 (0922): 17-17. ;  doi:
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Science & Technology Review. 2009, 27 (0922): 117-117. ;  doi:
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Science & Technology Review. 2009, 27 (0922): 125-125. ;  doi:
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Science & Technology Review. 2009, 27 (0922): 139-140. ;  doi:
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封面图片说明

Science & Technology Review. 2009, 27 (0922): 8-8. ;  doi:
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Abstract ( 512 )
半月科技风云

Science & Technology Review. 2009, 27 (0922): 9-9. ;  doi:
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Abstract ( 557 )
科技事件

Science & Technology Review. 2009, 27 (0922): 11-11. ;  doi:
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Abstract ( 540 )
科技工作者建议

Science & Technology Review. 2009, 27 (0922): 18-18. ;  doi:
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Abstract ( 541 )

Science & Technology Review. 2009, 27 (0922): 18-18. ;  doi:
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Articles

Gene cloning and sequence analysis of phenylalanine ammonia-lyase (PAL) in bamboo lignin synthase

Science & Technology Review. 2009, 27 (0922): 19-25. ;  doi:
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Abstract ( 691 )
PAL (phenylalanine ammonia-lyase, EC 4.3.1.5) is one of the key enzymes in the process of lignin synthesis. In this paper, PAL gene sequence from four vaireties of bamboo: Phyllostachys dulcis, Phyllostachys prominens, Phyllostachys pubescens heterocycla, and Pleioblastus maculosoides Wenwere obtained by RACE (rapid-amplification of cDNA ends). The results show that each PAL gene has two exons and an intron and every ORF (Open Reading Frames) is 2136 bp length, encoding 712 amino acids. And then the bamboo PAL amino acid sequences and three-dimensional structures were speculated and analyzed, the results indicate that all of the PAL proteins contain a large number of α-helix and β plated sheet structure. Neighbor-Joining phylogenetic tree based on PAL sequence of bamboo and other 27 plants indicated that PAL gene sequence in Bamboo is relatively conservative,and bamboo had very close relationship with that of Zea may and Saccharum officinarum , and far relationship with that of Capsicum annuum et al.

Green tea polyphenols prevents age-related learning and memory decline of C57BL/6J mice.

Science & Technology Review. 2009, 27 (0922): 26-31. ;  doi:
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Abstract ( 673 )
To investigate the effect of Green Tea Polyphenols (GTP) on the degeneration of learning and memory ability in aged C57BL/6J mice, 14 month old C57BL/6J mice were randomly divided into aged control group and three GTP administration groups GTP was dissolved into the drinking water with a concentration of 0.025%, 0.05% and 0.1%(W/V), respectively. After six months, the learning and memory abilities of the mice were checked by Morris water maze and step-down test. Thereafter, the serum of the mice was collected to measure the levels of SOD and GSH-PX. The protein levels of post synaptic density protein 95 (PSD95) and Ca2+/calmodulin-dependent protein kinase II (CaMKII) were examined using Western blot 0.05% and 0.1% GTP administration can significantly shorten the escape latencies and swim distances of the mice in a place navigation test, increase the time spending in the target quadrant and the crossing numbers in a spatial probe test, and increase the latency to step down in the step-down test. It is shown, 0.5% and 0.1% GTP administrations have significantly raised the activities of SOD and GSH-PX in the serum and prevented the age-related reductions of two representative post synaptic density proteins PSD95 and CaMKII. 0.05% and 0.1% GTP in the drinking water can significantly prevent the decline of learning and memory ability in aged C57BL/6J mice. Besides its antioxidant ability, GTP may also regulate some learning and memory related proteins.

Traditional Uighur Medicine Classification of Type-2 Diabetes Mellitus and the Neuro-Endocrine-Immune Disturbance

Science & Technology Review. 2009, 27 (0922): 32-37. ;  doi:
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Abstract ( 673 )
To observe the neuro-endocrine-immune system markers of T2DM in different abnormal body fluid syndromes and discuss the relations between abnormal body fluid syndromes and neuro-endocrine-immune systems, the levels of Cluster of Differentiation 4+ (CD4+), Cluster of Differentiation 8+ (CD8+), Narual Killer cell (NK), Interleukin-1β (IL-1β), Interleukin-6 (IL-6), Tumor Necrosis Factor-α (TNF-α), Adrenocorticotropic-Hormone (ACTH), Cortisol (CORT), Dopamine (DA), Noradrenaline (NE) were tested by using Flow Cytometer, radioimmunoassay method and Liquid Chromatography. Patients with abnormal savda T2DM make up 45.40% of T2DM, nearly amounting to the total percentage value of other three kind of abnormal body fluids. Compared to the abnormal khan group, the level of CD4+ was decreased in the abnormal savda group (P<0.01). Compared to the abnormal khan and belghem group, the level of NK was decreased in the abnormal savda group (P<0.01). Compared to the abnormal belghem, sepra and khan group, the level of IL-1β was increased in the abnormal savda group (P<0.05). Compared to the abnormal belghem and sepra group, the level of IL-6 was increased in the abnormal savda group (P<0.05). Compared to the abnormal khan and sepra group, the level of NE was increased in the abnormal savda group (P<0.05). There were no significant differences on the levels of DA, ACTH and CORT in patients with different body fluids (P>0.05). It is concluded that the abnormal savda syndrome is the main syndrome in type-2 diabetes milletus in Uyghur Medicine. Compared with other Uighur abnormal hilit groups in type-2 diabetes, the abnormal savda group has the most unbalanced immune system and its sympathetic nerve is activated mostly.

Detection of the Antigen IgG Microconcentration with Nanotechnology and Molecular Probes Technology

Science & Technology Review. 2009, 27 (0922): 38-43. ;  doi:
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Abstract ( 1559 )
With better understanding of the characteristics and conditions of the interaction between the gold nanoparticles and DNA, people are developing the bio-bar-code growth technology based on the gold nanoparticles. The method is widely applied to detect the level or microconcentration of some proteins, nucleic acid, cells and cytokines. New methods are coming into being with higher sensitivity as distinct from the PCR and ELISA. The bio-bar-code and the related technology based upon the gold nanoparticles are being continuously innovated. In this paper, the microconcentration of the antigen IgG is detected by applying nanotechnology and molecular probes technology in the experiment. The magnetic microbeads modified with the monocolon antibody are used to capture the target antigen IgG, to modify the gold nanoparticles with the polycolonal antibody and the avidin combined with the molecular beacons, thus to modify the biotin through the disulfide bonds at the T base position of the 3' terminal of the stem, and to amplify the signal in cascades. The magnetic microbeads can be combined with the gold nanoparticles through the detected antigen IgG. Then the DTT could cut the MB off the gold nanoparticles through the reduction effect and the free MB can be hybridized with its target sequence. Then the fluorescence density is measured with Spectrofluorometer. The results show that there are some relationships between the fluorescence density and the concentration of the antigen IgG. The detection sensitivity of the research is very high, which reaches 1pg/ml, about the 6.67 fM.

Extraction of Information of Standing Tree Images Based on Region Growth and Edge Detection

Science & Technology Review. 2009, 27 (0922): 44-47. ;  doi:
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Abstract ( 1908 )
The extraction of information of standing tree images provides a fast and precise way for management of the forest resource inventory, also provides an important basis for pre-harvest assessment. Methods are proposed in this paper to acquire images of standing trees in real-time, to extract relevant features and to achieve fast recognition without destruction. Thus the rich information can be easily preserved and accessed based on intuition. So it provides a basis for the automation of a forest resource inventory management system, and at the same time, for the improvement of the traditional methods in the forest resource inventory and technology, which also reduces the labor intensity in field investigations. A tree measurement system is proposed to achieve the automatic and precise management of forest resources survey, as an enhancement of the traditional survey methods and techniques. A method of extracting the calibration stick by color components is proposed. First, using a tripod to keep the camera in the horizontal plane, i.e. to make sure that the imaging plane is parallel to the middle curve of the stem volume and normal to the ground. The images of the standing tree can thus be taken. Then a region growth algorithm is applied to search the tree contour. Region growth approach is adopted to achieve the image segmentation, where neighboring pixels are examined and different choices of seeds may have different segmentation results. According to the shape characteristics of the tree trunk, a seed pixel is chosen from the stem base. Then the main trunk is extracted by mathematical morphology. Finally the information of the diameter at the breast height, the diameter of the main branch and the branch height are determined according to photogrammetry and the parameters of the calibration stick. Experimental results show that these methods can effectively segment the calibration stick and the tree contour. It is convenient to obtain accurately and automatically the standing tree information.

The Influence of Characteristic Dimension upon Movement of Explosion-Driven Inert Metal Particles

Science & Technology Review. 2009, 27 (0922): 48-53. ;  doi:
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Abstract ( 1047 )
The charge made of a mixture of explosive and dense inert metal particles is a kind of special heterogeneous explosive. After explosion, the particles driven by the explosion will reach a high speed, and can destroy the target in a certain direction and range. As the speed of inert metal particles decreases quickly, the flying distance of the particles can effectively be controlled. Reducing the amount of explosives can reduce the power of blast. Therefore, the destruction area can thus be controlled. In order to effectively control the destruction area and distance of the inert particles, we must know more about the movement of the particles in the explosion. The positions and shapes of particles in the explosive are very important in the dispersal mechanism. With the finite element code AUTODYN, a model of detonation driven single metal particle is established. Numerical simulations and comparative analyses are carried out, to study the movement of particles with different initial positions, radii and shapes. The analytical results provide some information on dense inert metal explosives.

Overall Soft Landing Installation of Offshore Wind Turbine

Science & Technology Review. 2009, 27 (0922): 54-57. ;  doi:
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Abstract ( 669 )
This paper analyses the effect of ocean wave loading on the wind turbine installation, and proposes a kinematic model for the wind turbine under the ocean wave loading, with which some simulations are carried out. A scheme of wind turbine soft landing is put forward according to the installation requirements and simulation results. The wind turbine movement states of the various stages are analyzed. Hydraulic accumulators are used as buffer storage devices, so the hydraulic cylinders can quickly follow the movement of the turbine interface frame, with only one impact during the landing. A control mode is proposed to combine the hydraulic proportional control technology with the acceleration feedback, which not only can accomplish a buffer action and make the buffer acceleration controllable in a closed loop, but also can be switched to the mode of synchronous movement to adjust the wind turbine gesture. Comparing with a completely passive buffer, which is not controllable, and difficult to adjust the gesture of the wind turbine and to accommodate different modes, it has greatly enhanced the flexibility of installation and achieves a soft landing for the wind turbine installation. At the same time it also has laid a foundation for further research of its control algorithm and reliability.

Vibration Stability of Automotive Powertrain Mounting System

Science & Technology Review. 2009, 27 (0922): 58-62. ;  doi:
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Abstract ( 1074 )
Vibration of the powertrain mounting system is a key factor that affects the Noise Vibration and Harshness (NVH). How to effectively optimize the vibration of a powertrain mounting system is an important task for the control of NVH. This paper presents results of the project carried out by the Great Wall Automobile Group to optimize the vibration noise of a family car. This paper covers the following aspects: (1) experimental study, such as mass center, principal axis of inertia and moment of inertia, confirmation of suspending component installation site, stiffness and damping characteristic parameter, etc. (2) analyses of engine excitation, primarily the calculation of inertia force of linkage piston mechanism. (3) establishment of a model for kinetic analysis of the powertrain mounting system by Automatic Dynamic Analysis of Mechanical Systems (ADAMS). (4) the establishment of the system's simulation model on the basis of testing a family sedan's powertrain mounting system and analysis of the system incentive. In a variety of conditions, dynamic simulations are carried out for the powertrain mounting system. For analyzing the system characteristics and patterns of vibration, the introduction of amplification factor and the stability margin helps the analysis and evaluation of the vibration of the powertrain mounting system.

The study on water flooding response and its affecting factors by numerical simulation

Science & Technology Review. 2009, 27 (0922): 63-65. ;  doi:
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Abstract ( 645 )
Because the pressure propagation in earth completes instantly, the water flooding response is re-defined as the time when the ratio of the result of flood development deliverability minus resilience development deliverability and resilience development deliverability reaches one percent. With the modified definition, the single phase flow's water flooding response and its affecting factors in a five-spot water flooding pattern are studied by numerical simulations when the production well is an infinite conductivity vertical fracture well and the injection well is a straight well. Permeability greatly affects the water flooding response, and water flooding response sharply increases with decrease of permeability, especially when the permeability is smaller than 10 md. The bigger the well spacing, the longer the water flooding response, and the increase of water flooding response is getting faster with spacing's increase. The higher the injection volume, the shorter the water flooding response, and the decrease of water flooding response is getting smaller with injection volume's increase. Measures can be taken such as injection ahead of time, with smaller well spacing and higher injection volume when permeability is too small.

Study on Thermal Properties of Sulfide Ores by Using Thermogravimetric and Differential Scanning Calorimetric Method

Science & Technology Review. 2009, 27 (0922): 66-71. ;  doi:
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Abstract ( 700 )
In order to evaluate the spontaneous combustion tendency of sulfide ores, the oxidation and decomposition behavior of two samples (marked by No. 1, No. 2) were analyzed. The contents of different minerals in the ores were measured by both Thermogravimetric analysis (TG) and Differential Scanning Calorimetry analysis (DSC) at heating rates of 5, 10 and 15℃/min. The curves of TG, DTG and TG-DTG-DSC for each sample under different conditions were determined. Their combustion characteristic parameters were obtained, including the ignition points, temperature intervals of heat-absorption (radiation) and weight-gain (loss). The reaction activation energy for No. 1 and No. 2 samples was calculated by the Flynn-Wall-Ozawa method, with the results of 387.32 and 448.50 kJ/mol, respectively, which shows that a complement of TG method and DSC method is well achieved; the whole reaction process of sulfide ores can be reflected by their joint application; the gained activation energy can be used as indexes to evaluate spontaneous combustion tendency of sulfide ores under the condition of multiple samples being measured at the same time.

Natural Gas Well with Hydrogen Sulfide

Science & Technology Review. 2009, 27 (0922): 72-75. ;  doi:
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Abstract ( 756 )
With the heavy dependence of domestic economy on oil and gas, the exploitation of natural gas fields with hydrogen sulfide is an urgent project in China. The quantitative risk assessment for natural gas wells with hydrogen sulfide is a necessary and impending requirement. A quantitative calculation method for an individual risk for leakage and dispersion process of hydrogen sulfide in blowout of gas wells is proposed in this paper. Based on the statistical analysis of data in literature, the probability of blowout incident is brought forward for reference. The method is applied to a typical gas well in Sichuan and Chongqing district as a practical example. The contour curves of individual risks in the area around the well are obtained, and compared with the acceptable level of the individual risks. The results show that the topographic conditions of the gas well greatly influence the calculation results of the individual risks, the distance between the upper limit isoline of acceptable risk and the well in different directions can reach 1 000 m. So it must be fully considered when performing the quantitative risk assessment of gas wells. This method offers an effective technical measure for administration departments and enterprises to conduct quantitative risk assessments and risk managements during the exploitation process of natural gas fields with hydrogen sulfide. The method can be used in dividing emergency planning zones and deciding the boundary for natural gas wells with hydrogen sulfide.

Study on Fire Risk Evaluation System Based on Analysis of Ability and Frangibility

Science & Technology Review. 2009, 27 (0922): 76-80. ;  doi:
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Abstract ( 652 )
Fire risk evaluation is an important issue for a society. This paper proposes a method of fire risk evaluation, based on analysis of ability and frangibility. In a fire risk evaluation index system, the basic cells are evaluated through an expert grading system, the weighted values of all levels of indexes are determined through the Analytic Hierarchy Process, and based on the calculation and analysis of protection ability and damage potential, the risk level of the evaluation object is determined. As an example, the fire risk evaluation of the National Stadium as an example is carried out, which shows that this evaluation method can be applied to large building engineering. Some issues related to the applications of this method are discussed. The method can be used for the fire risk evaluation for large public buildings, and plays a part in improving fire protection level and perfecting building fire risk evaluation method system.

Safety Monitoring and Emergency Platform for Chemical Industry Parks

Science & Technology Review. 2009, 27 (0922): 81-85. ;  doi:
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Abstract ( 1111 )
In recent years, the number of chemical industry parks increases greatly, and the park format has become one of chemical industry development trend in our country. A chemical industry park has the following features: relatively crowded enterprises, a great variety of chemistry products, complicated chemical industry processes, gigantic device scales and harsh operation conditions, which involves large number and high density of major hazards and with serious extraordinarily big accident risks. Therefore, the building of a safety monitoring and emergency platform for a chemical industry park is of great importance. The platform can achieve early warnings for accidents and help decision-making for emergency rescue operations based on the monitoring the fixed hazards, dangerous chemical industry processes, chemicals vehicles and major parts of public areas. Based on the major hazards monitoring and supervising system and the emergency rescuing system of our country, the paper focuses on the building scheme of the platform. Firstly, the overall architecture of the safety monitoring and emergency platform for chemical industry parks is presented. Secondly, the hardware structure of the platform and the monitoring workflow of chemicals vehicles are introduced. Finally, the software design ideas and software functions are put forward.

Comparative Study on Large-scale Circulation and Structural Characteristics During Rich and Rare Meiyu Years in North-Central of Zhejiang Province

Science & Technology Review. 2009, 27 (0922): 90-98. ;  doi:
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Abstract ( 1105 )
With available data of rainfalls, the large-scale circulation and structural characteristics during rich and rare Meiyu years in north central of Zhejiang Province in 2007 and 2008 are comparatively analyzed. The results are as follows. (1) The years of 2007 and 2008 are, respectively, the typical rare Meiyu year and rich Meiyu year, with the former's rainbands being situated in Huaihe river basin and the latter's rainbands in north central of Zhejiang Province. (2) Although it is the same weather system in troposphere, the location of subtropical westerly jet and ridge line of southern Asia high is northerly in rare Meiyu year while southerly in rich Meiyu year. In rare Meiyu year, the west flow of low-level which comes from the Bay of Bengal steers in South China Sea and transports water vapor to Huaihe river basin, does not combine with the southeast flow which comes from southwest of subtropical high; while in rich Meiyu year, the southwest flow from South China Sea transports to Zhejiang and Fujian coastal regions and combines with southeast flow from western Pacific. The subtropical high is westerly and the west ridge point of 588 line is close to 118°E and it blocks the weak cold air in rare Meiyu year while in rich Meiyu year, the subtropical high is easterly and the west ridge point of 588 line lies at 124°E, favorable to form a water vapor channel in Zhejiang and Fujian coastal regions. (3) Comparative analysis of the structure of Meiyu front between rich and rare Meiyu years indicates that the temperature is relatively low and there is no obvious temperature gradient, while the gradient of equivalent potential temperature and moisture is quite significant. In rare Meiyu year, the dense band of equivalent potential temperature has a zonal distribution and is abnormal northerly, while in rich Meiyu year, it is southerly with a distribution from southwest toward northeast. With respect to the vertical profile, the convergence on low-level and divergence on upper-level in rich Meiyu year are even more obvious than those in rare Meiyu year, with an extended region of positive vorticity.

A Kind of Intrinsically linked graphs with knotted components

Science & Technology Review. 2009, 27 (0922): 99-101. ;  doi:
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Abstract ( 633 )
The spatial graph theory is a natural generalization of the knotted topology theory, as an active branch of the topology. In recent years, intrinsically linked and intrinsically knotted graphs, as very important graphs in spatial graphs, are becoming targets of some relatively new research areas. The study of intrinsic linking and knotting began in 1983 when Conway and Gordon showed that every embedding of K6 (the complete graph on six vertices) contains a non-trivial link, K6 is an intrinsically linked graph, every embedding of K7(the complete graph on seven vertices) contains a non-trivial knot, K7 is an intrinsically knotted graph. This paper combines the two properties of intrinsic linking and intrinsic knotting together, constructs a graph with those two properties, as an intrinsically linked graph with knotted components such that every spatial embedding of this graph contains a non-split link, where at least one of the components of this link is a nontrivial knot. To construct the Petersen graph P8, this paper uses the method of forming the graph with two graphs K3,3,1 and edges. A kind of intrinsically linked graphs with knotted components F(104) is obtained.

A Proof of Hausdorff Dimension of Cantor Set

Science & Technology Review. 2009, 27 (0922): 102-104. ;  doi:
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Abstract ( 761 )
This paper proposes a different method of proving Hausdorff dimension of Cantor set by considering character string or metric space. Using the principle of set finite covering and Lipschitz mapping, a mapping is constructed from the metric space that is defined by character string to Cantor set. The recurrence relationships are analyzed for the above mapping, which is shown to satisfy the biaxial Lipschitz inequality. It is proved that Hausdorff dimension of the metric space and that of Cantor set are equivalent. A method is found to prove Hausdorff dimension of Cantor set, which is different from the mass distribution principle, provides a way to avoid considering a suitable mass distribution, which is difficult, especially for the lower bound of the Hausdorff dimension, on its fractal set when applying the mass distribution principle for other complicated fractal sets, also has laid a theoretical foundation for studying the theories and methods for proving Hausdorff dimension, and the relations between character string and dimension.

Application of Cotree in Topological Classification of Graphlike Manifold

Science & Technology Review. 2009, 27 (0922): 105-107. ;  doi:
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Abstract ( 686 )
The graphlike manifold M(G) is a tubular surface with the frame of a simple connected graph G. This paper studies the enumeration problem of homeomorphic equivalence classes of the graphlike manifold, which can be transformed into a 2-edge-coloring enumeration problem for graphs. A new approach is proposed in this paper, based on the cut space and the cycle space in the graph theory. It is well known that the enumeration theory of graphs is composed of two parts: the enumeration of labeled graphs and that of unlabelled graphs. Generally speaking, the former is easier than the latter (as the latter involves isomorphism transformation). The enumeration formula and related results of labeled graphs are obtained by means of the group theory in the paper. The enumeration based on the cycle space and the cut space in the graph theory not only simplifies the proofs based on the group theory, but also better reveals the relation between homeomorphic classes and the cycle-structure of graphs. Based on the definition of cotree a new kind, named "cotree scheme", is proposed. It is found that a transverse of T-classes can be constructed by taking all edge-induced subgraphs of the cotree as the black subgraphs. A representative system of H-classes can be constructed by taking all non-isomorphic edge-induced subgraphs of the cotree as the black subgraphs.
Reviews

Advances in Research on Hesperidin

Science & Technology Review. 2009, 27 (0922): 108-115. ;  doi:
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Abstract ( 867 )
The study on Hesperidin is recently very hot in the fields of food, medicine and personal care product industries. Hesperetin flavone mainly exists in natural plant Fructus Aurantii Immmaturus, Pericarpium citri reticulate, Citrus peel, and so on. It has various physiological activities: antibiotic, anti-inflammation, antiviral; prevention of cardiovascular disease; relaxant effects on gastrointestinal smooth muscles; reinforcement of Vitamin C; anti-oxidization of free radicals; inhibitor of central nervous system; reducing cholesterol; improvement of skin quality; anti-Osteoporosis; anti-cancer, and others. This paper studies the main functions of hesperidin, the main materials for extraction of hesperidin, and the extraction and purification technologies. The extraction methods include boil water extraction; alkali-extraction and acid-precipitation; alcohol extraction and acid precipitation; water extraction and resin adsorption. By using property modification technology, one could prepare water soluble hesperidin, hesperetin, persicogenin, diosmin, diosmetin, methylhesperidin, hesperidindihydrochalcone, luteolin, eriodictyol, orobol, neohesperidin flavonoid, and others, which will help the study on hesperidin flavonoid.

Science & Technology Review. 2009, 27 (0922): 116-116. ;  doi:
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Focus

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科技评论

Science & Technology Review. 2009, 27 (0922): 120-120. ;  doi:
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主编心语

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走向职场

Science & Technology Review. 2009, 27 (0922): 126-126. ;  doi:
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Science & Technology Review. 2009, 27 (0922): 133-137. ;  doi:
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