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   Science & Technology Review
2009, Vol.27, No. 0920
28 October 2009

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To Carry Forward Humanistic Spirit of Scientific and Technical Worker

Science & Technology Review. 2009, 27 (0920): 1-1. ;  doi:
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Abstract ( 518 )
特别栏目

Science & Technology Review. 2009, 27 (0920): 8-8. ;  doi:
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Science & Technology Review. 2009, 27 (0920): 10-10. ;  doi:
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Abstract ( 499 )

Science & Technology Review. 2009, 27 (0920): 12-13. ;  doi:
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Science & Technology Review. 2009, 27 (0920): 14-14. ;  doi:
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Science & Technology Review. 2009, 27 (0920): 15-15. ;  doi:
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Abstract ( 469 )

Science & Technology Review. 2009, 27 (0920): 16-16. ;  doi:
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Abstract ( 451 )

Science & Technology Review. 2009, 27 (0920): 17-17. ;  doi:
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Abstract ( 475 )

Science & Technology Review. 2009, 27 (0920): 117-117. ;  doi:
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Science & Technology Review. 2009, 27 (0920): 124-124. ;  doi:
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Science & Technology Review. 2009, 27 (0920): 125-125. ;  doi:
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Science & Technology Review. 2009, 27 (0920): 139-140. ;  doi:
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Abstract ( 449 )
封面图片说明

Science & Technology Review. 2009, 27 (0920): 8-8. ;  doi:
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Abstract ( 456 )
半月科技风云

Science & Technology Review. 2009, 27 (0920): 9-9. ;  doi:
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Abstract ( 491 )
科技事件

Science & Technology Review. 2009, 27 (0920): 11-11. ;  doi:
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Abstract ( 450 )
科技工作者建议

Science & Technology Review. 2009, 27 (0920): 18-18. ;  doi:
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Abstract ( 540 )
Articles

Effects of Drift Due to Chamber's Long-time Usage on Microcrystalline Silicon Properties

Science & Technology Review. 2009, 27 (0920): 19-21. ;  doi:
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Abstract ( 570 )
This paper investigates the drift of microcrystalline silicon (μc-Si∶H) thin film properties due to the chamber's long-time usage in plasma enhanced chemical vapor deposition (PECVD). The condition parameters were controlled to reach about 0.5 nm/s deposition rate for the samples to have a certain crystalline degree, 40%~80%, as detected and estimated by two different wavelength lasers in Raman scattering measurement. The samples under different silane concentrations (i.e. the flow rate ratio, [SiH4]/([SiH4]+[H2])) were compared carefully, and it is found that both their deposition rate and crystalline degree increase with the chamber usage time, which was used as an independent variable in this experiment. This phenomenon may be explained by the accumulated silicon remains such as powders and films, observed on the electrode plate and/or on the chamber wall in this experiment. These silicon remains probably take part in the reactions related to the film formation in plasma. It is found that this drift of μc-Si∶H structural and electronic properties can be adjusted by increasing the silane concentration, and with the deposition rate being kept at a high level.

Reconstructed Pelvis with Autogenous Lower-extremity Long Bones after Hindquarter Amputation: Biomechanical Analysis in the Sitting Posture

Science & Technology Review. 2009, 27 (0920): 22-26. ;  doi:
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Abstract ( 626 )
After hindquarter amputation, the pelvis reconstruction using abandoned autogenous lower-extremity long bones is an effective biological reconstruction method. However, the bio- mechanical effects of this reconstruction have never been well studied. The objective of the present study is to estimate the feasibility of the operation using the finite element simulation, and to analyze the stress distributions before and after the reconstruction under sitting posture. Two operative schemes, the ischiadic tuberosity replacement with condyles of femur and tibial plateau, respectively, are considered. With additionally the intact model, three finite element models are constructed, and the intact model is validated through stress and displacement measurements in a cadaver specimen. Normal sitting posture is considered in the simulations of these models, and von Mises stresses are used as indexes in comparison. The stress distributions are found to be significantly different before and after the reconstructions. In the model of condyles of femur reconstruction, severe stresses are mainly distributed at the contact surface between femur and the facies auricularis of the left sacral bone, the right iliosacral articulation, and the left long bar. In the model of tibial plateau reconstruction, the peak stresses in the remained iliac and sacral bones, the bridging bone, and long bar are greater than those in the model of condyles of femur reconstruction. Compared with the peak stress in the grafted femur of the latter model, the peak stress in the tibial of the former model is distributed at the shaft of bone, with a broader distribution area. From the view point of biomechanics, the reconstruction with condyles of femur shows a better performance. In the operation design, the diameter of long bars should be appropriately great, and the rigidity of the bars should be reduced as long as a sufficient strength is allowed.

Numerical Simulation of Human Thoracic Aorta Based on CT Images

Science & Technology Review. 2009, 27 (0920): 27-31. ;  doi:
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Abstract ( 619 )
In order to provide a theoretical basis for the clinical treatment of thoracic aortic aneurysms, a 3D finite element model of thoracic aortic aneurysm is constructed, including ascending aorta, aortic arch, and descending aorta, with a fusiform aneurysm in descending aorta, together with three large branches (innominate artery, left common carotid artery, and left subclavian artery). Numerical simulations of hemodynamics for this model is carried out. Based on the clinical patient-specific CT data of thoracic aortic aneurysm, image segmentation is carried out by MIMICS 11 and an optimized surface model of thoracic aortic aneurysm is constructed, which is imported into ANSYS ICEM CFD 11.0, where the volume meshes and boundary layer meshes are generated, and CFD analysis is performed. Numerical simulation is performed using a finite volume method. A finite element model for hemodynamics analysis of patient-specific thoracic aortic aneurysm is built. Distribution and changes of streamlines, velocity vector, pressure and wall shear stress are obtained for the patient-specific model. Such models with digital and patient-specific features can be applied to hemodynamic analysis of thoracic aortic aneurysm. Rupture mechanism of thoracic aortic aneurysms in a patient can be analyzed based on this kind of models.

Clinical Application of Endoscopic Thyroidectomy via Anterior Chest

Science & Technology Review. 2009, 27 (0920): 32-35. ;  doi:
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Abstract ( 893 )
To explore its possibility and significance, the thyroidectomy under laparoscopy, was performed for 15 cases with thyroid neoplasms, partial thyroidectomy for 6 cases with nodular goiter, and subtotal thyroidectomy for 2 cases with primary hyperthyroidism. All patients were followed up for 1 year. 24 cases are successful without injury of nerve and parathyroid gland, 1 case is transferred to open operation due to bleeding, which turns out successful. The operation time ranges from 62 to 210 minutes, with an average of 90 minutes. The bleeding in operation is 5 to 40 mL and the post-operational hospitalization takes 5 days. No complication was observed in 1 year's follow-up. No recurrence was developed in primary hyperthyroidism cases. It is concluded that the thyroidectomy under laparoscopy is safe with good cosmetic effect.

Clinic Analysis of 28 Cases of Syrinx-shunting by Pressure Determination of Intra/Extra Syrinx

Science & Technology Review. 2009, 27 (0920): 36-38. ;  doi:
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Abstract ( 551 )
To study the effect of syringe-shunt with T tube by pressure determination of intra/extra syrin, the pressures of intra/extra syringx of 28 syringomyelia cases were measured during the operation. In these cases, 21 syringomyelia cases were practiced by syringe-peritoneal shunt with T tube, and 7 cases were practiced by syringx-peritoneal shunt. The clinical symptoms and imaging data were analyzed during the follow-ups ranging from 3 months to 4 years (1.9 years on average). The clinical symptoms were significantly improved, with an improvement rate of 84.8%. The imaging follow-up studies show that all of patients' syrinx cavities are significantly shrinked. Among these cases, syrinx has disappeared completely in 9 cases, and in other 19 cases it is shrinked. Effective rate of shunt is 100%. The results show that it is a reasonable and reliable method to treat the syrinx cavity by using syrinx-shunting by pressure determination of intra/extra syrinx with T tube.

Metabonomic Differences of Plasma Between Abnormal Savda and Unsavda Syndrome Neoplasm Patients

Science & Technology Review. 2009, 27 (0920): 39-43. ;  doi:
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Abstract ( 1370 )
The metabonomic differences of plasma between abnormal savda and unsavda syndrome neoplasm are studied in light of the traditional Uighur medicine. Plasma samples were obtained from 80 cases of abnormal savda syndrome neoplasm patients and 160 cases of abnormal unsavda syndrome neoplasm patients. For each sample, the 1H Nuclear Magnetic Resonance (NMR) based metabonomic analysis was performed and the obtained data was analyzed by the Orthogonal Partial Least-Squares Discriminant Analysis (OPLS-DA). The results show that the abnormal savda syndrome neoplasm patients have a lower degree of glucose, Very Low Density Lipoprotein (VLDL), unsaturated lipids, alanine and a higher degree of fatty acid metabolites like acetone, acetoacetate, β-hydrocxy butyrate, isobutyrate; product of glycolysis like lactate, pyruvate; amino acids like leucine, tyrosine, isoleucine, valine, acetylcysteine; another metabolites like myo-inositol,glycoprotein in plasma than the unsavda syndrome neoplasm patients(P<0.05). These findings indicate that the abnormal savda syndrome neoplasm patients have a higher degree of fat mobilization and glycolysis level, their immune function is more seriously damaged and their prognosis may be worse than that of abnormal unsavda syndrome neoplasm patients.

Self Adaptive Filtering Based on Interference Suppression Game in Mobile Ad hoc Network

Science & Technology Review. 2009, 27 (0920): 44-49. ;  doi:
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Abstract ( 906 )
Mobile Ad hoc Network (MANET) is a centerless packet radio network without any fixed infrastructure. It relies on a coordination between nodes to establish such kind of network in mobile and complex wireless environment with multi-hop forwarding way to remedy the defect of the limited transmission distance so as to broaden the network coverage and provide various services. In recent years, tremendous progress has been made with respect to capabilities of self-configuration and self-maintenance. However, the attenuation and the interference caused by node mobility and wireless channel sharing weaken the stability of communication links. The negative impact on communication performance in mobile Ad hoc network caused by limited bandwidth, high bit error rate, fade, noise, interference and so on, is alleviated by a self adaptive filtering game based on frequency sub-bands and predetermined threshold obtained in Gauss and multipath fading channel according to frequency-matching principle and BER performance. This game uses sub-bands dynamically without frequency hopping techniques is introduced to greatly increase frequency spectrum utilization efficiency and to provide some new insight in improving communication performance. The effectiveness of the self adaptive filtering method has been verified by ISS-OFDM in different interference conditions, and the simulating result based on NS2 indicates that the system bit error rates can be improved as far as by 5 dB.

Theoretical and Numerical Analysis of the Response of Rock Mass Surrounding Tunnel Based on the Nonlinear Failure Criterion

Science & Technology Review. 2009, 27 (0920): 50-54. ;  doi:
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Abstract ( 556 )
The Hoek-Brown nonlinear criterion is used to describe the nonlinear failure characteristics of rock mass. The effect of rock strength, structure plane characteristics and stress state on the rock mass strength is studied. In the theoretical analysis, the stress and the deformation of the rock mass are obtained. The numerical calculation method and the calculation model of tunnel based on the Hoek-Brown criterion are established and used to numerically study the stress and deformation in the rock mass surrounding the tunnel after excavation. A comparison is made between the theoretical results and the numerical results, for the radial stress, tangential stress, shear strain distribution, plastic zone distribution and the displacement, with the following conclusions. (1) The excavation of tunnel will cause the disturbance of the surrounding rock mass, turning the equilibrium state into a non-equilibrium state. With time, the unbalanced force will be dissipated to the rock mass and the disturbance in the rock mass will become smaller and finally the state of equilibrium is returned. (2) The results from the numerical analysis is larger than those of theoretical analysis, but the differences is small.

Dynamic Analysis and Numerical Simulation Based on the Turntable of the Hydrostatic Support System

Science & Technology Review. 2009, 27 (0920): 55-59. ;  doi:
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Abstract ( 981 )
In this paper, a finite element model of a turntable of the Hydrostatic Support System is established according to engineering practice. The springs, with the action of the oil-film force, are added to the turntable model. The dynamic property of the turntable is analyzed with the numerical simulation. The effect of the number of oil chambers on the frequency of the turntable is studied under two different situations, that is, a constant oil supply of the single oil chamber and the constant total oil supply. In a certain range of oil supply, under the situation of a constant oil supply of every single oil chambers, the vibration frequencies of the turntable, as the Hydrostatic Support System with different number of oil chambers, increase with the increase of the number of the oil chambers and the oil supply value, and the increase is nonlinear. Under the constant total oil supply, the effect of the number of oil chambers on low order vibration frequencies of the turntable can be ignored when the number of the oil chambers is more than six. These studies serve a basis for further studies on dynamic properties of the whole system.

Synthesis, Structure Characterization and Applicationof PP of Chemical-composite Sorbitol Acetal Nucleators

Science & Technology Review. 2009, 27 (0920): 60-64. ;  doi:
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Abstract ( 677 )
Chemical-composite sorbitol acetal nucleators were firstly synthesized with sorbitol, mixed with aldehydes of p-chlorobenzaldehyde (PCBA) and p-tolualdehyde (PTA) as raw materials and p-methyl benzenesulfonic acid as catalyst. Under the molecular ratio 2.05:1 of mixed-aldehydes to sorbitol, eight chemical-composite nucleators, with molar ratios 1∶0(E1), 4∶1(E2), 3∶1(E3), 2∶1(E4), 1∶1(E5), 1∶3(E6), 1∶4(E7), and 0:1(E8) of PBCA to PTA, respectively, were synthesized and their crystal and molecular structures were characterized by X-Ray Diffraction (XRD) and FTIR(Fourier transform infrared spectroscopy), separately. FTIR results show that synthetic products are sorbitol acetal, and XRD results indicate that the crystal structures of sorbitol acetal manufactured by mixed-aldhydes are different from E1 synthesied by PBCA. Melting point tests show that the MP of the chemical-composites decreases with the decrease of PBCA molar fraction within the reaction mixed aldehyde, and as a result, it will obviously reduce the processing temperature of polypropylene. The application experiments of nucleators synthesized in homopolypropylene(HOPP) show that the chemical-composites have enhanced HOPP stiffness and transparency simultaneously.

Intercalation Assembly and Characterization of the Supramolecular Structure of Maleic Acid Anions Column Pillared Layered Double Hydroxides

Science & Technology Review. 2009, 27 (0920): 65-68. ;  doi:
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Abstract ( 920 )
Mg-Al Layered Double Hydroxides (Mg-Al-LDHs) have unique structural memory effect. Used it as front body, maleate anions were inserted into layers by back mixing precipitation method. The maleic acid anions column pillared hydrotalcites were synthesized. The samples prepared were characterized by X-Ray Diffraction (XRD), Fourier transform infrared (FTIR) and Differential Thermal Analysis (DTA). The results show that the initial interlayer carbonate ions can be completely replaced by the maleic acid anions under controlled condition. The expansion of the inter layer spacing from 0.76 nm to 1.10 nm, with nanoscale supramolecular structure. As can be seen from FTIR and XRD, maleic acid anions were inserted into the space between layers in spite of action force between layers, held open layers. This generated stronger interaction force with layers. Supermolecular structure of column pillared LDHs of maleic acid anions were weaker interaction force between layers. The object and main body were linked by ion bond, hydrogen bond and van der Waals gravitation and arranged regularly. Inorganic organic composite materials of column pillared with supermolecular structure were assembled. The structure models were presented. Thermal stability was improved. It is 465℃.

The Identification of Feathery Dunes

Zhibao DONG
Science & Technology Review. 2009, 27 (0920): 69-75. ;  doi:
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Abstract ( 963 )
Chinese scholars are paying unprecedented attentions on feathery dunes in recent years in their studies on the Kumtagh Desert, but with widely divergent views on feathery dunes. This paper reviews dune classifications proposed by several authors. It is shown that a feathery dune is a variation of a compound linear ridge, in which the main ridge acts as a "shaft" and subsidiary dunes diverging from the main ridge act as "feathers". Comparing the morphology of the feather dunes reported in other deserts around the world and that in the Kumtagh Desert of China, one may see that the so-called feather dunes in the Kumtagh Desert are in fact not real feather dunes, but typical seif dunes. The "feathers" erroneously assumed on remote sensing images are patterns reflecting albedo contrast of the ground surface sediments. They are not related to the relief on the inter-seif dune corridors. Feather dunes are developed in the complex wind regime under the condition of insufficient sand supply. That misconception of feather dunes held by some Chinese scholars should be corrected.

A Calculation Method for Urban Heat Island Intensity: A Case Study on Hefei City

Science & Technology Review. 2009, 27 (0920): 76-79. ;  doi:
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Abstract ( 774 )
Urban heat island is a phenomenon related with the fact that the urban upper air temperature is higher than the surrounding area. The intensity of the urban heat island is an important index for the urban heat environment. But there is few studies on the calculation of the urban heat island intensity at present. In this paper, the brightness temperature of the case image in Hefei city is calculated based on the theory of Remote Sensing. The urban construction land is considered at the same time. The spatial distribution of the urban heat environment is analyzed and a calculation formula is obtained by using the fractal theory and the improved radius method. It is shown that there is a jump in the horizontal distribution of the brightness temperature between the urban built-up area and non-built up area. Then the intensity of the urban heat island is computed. The attention is focused on the spatial distribution features of the urban heat environment. This method avoids the confusion of having to find the temperature in the suburban, and it is an important point in the studies on the intensity of the urban heat island.

Facilitative Effect of the Picture Superiority Effect During Encoding and Retrieval

Mi Li Ping
Science & Technology Review. 2009, 27 (0920): 80-86. ;  doi:
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Abstract ( 589 )
In order to investigate the picture superiority effect, we compared the ERP between picture combined word (picture-word) and pure word (word) during encoding and retrieval. During encoding, FN400 was more negative and lasted longer for picture-word than for word. Late positive component (LPC) was more positive and distributed broadly for word compared to picture-word. During retrieval, old picture-word elicited remarkably FN400 familiarity effect and parietal old/new effect compared to old word. We suggested that simultaneous image and verbal encoding of picture-word elicited better and faster recollection compared to word during the memory test. Our results demonstrated that the picture superiority effect was related to the ability of pictures enhancing encoding and facilitating recollection.

Life Estimation of Deep Bomb Storage Based on Constant Stress Accelerated Life Testing

Science & Technology Review. 2009, 27 (0920): 87-90. ;  doi:
Full text: HTML (0 KB)  PDF  (402 KB)  ( 331 )
Abstract ( 839 )
To predict the acoustic homing torpedo’s geometric range under different hydrological condition, it is presented that a method which using sound ray’s density to determine geometric operation range. This method is based on the Snell law of the acoustic propagation in water. It utilizes the different velocity gradient among the linear layers, it is realized that drawing the sound ray picture and building the mathematical model about the geometric operation range. It predicts the geometric homing range through sound ray density. The result proves that this design has a good effect on the trial.

The Causes of Heavy Rainfall in Weihai in July 2008

Science & Technology Review. 2009, 27 (0920): 91-96. ;  doi:
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Abstract ( 1319 )
By employing the NCEP/NCAR reanalysis data and routine observation data, the causes of heavy rainfall in Weihai on 19 and on 24 July 2008 are analyzed. It is shown that the establishment and the maintenance of the blocking anticyclone over Northern Asia lead to the southward movement of the westerly frontal zone and the dry cold air. The changes of the general circulation enhance the torrential rain over Weihai. The rainstorm processes are the result of the joint action of the high-level cold vortex and the low-level shear line or low pressure. It is also revealed that once the dry cold air meets the moist warm air over Shandong Peninsula, the heavy rainfall develops. The vapor comes from the East Sea and Yellow Sea. The vapor convergence comes into existence in Shandong Peninsula and plays a crucial role in the maintenance of the strong precipitation. In the period of rainstorms, the convergence in the underlying bed and the divergence in a high-level are characteristic of a divergence distribution. The convective ascending movement and the strong updraft found over 800 hPa and below 400 hPa provide a favorable dynamic condition for the rainstorms. The sufficient high energy of the potential pseudo-equivalent temperature θse in the rainfall region, the energy frontal zone in the northwest of the high energy area and the moisture provide the thermal condition for the formation of heavy rainfall.

Influence of Anode Flow Field on the Performance of Micro Direct Methanol Fuel Cell

Science & Technology Review. 2009, 27 (0920): 97-101. ;  doi:
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Abstract ( 1531 )
Recently, the direct methanol fuel cell (DMFC) has been drawing an increasing attention of researchers to the power applications of advanced portable electronics, because of its advantages such as high theoretical power density, good efficiency, relatively simple system features and convenience in use. The design of its flow field is one of key factors for DMFC performance. In this paper, a non-equipotent flow field, with the channel width being gradually changed along the channel length, is designed. Transparent DMFCs with different flow fields are designed and fabricated. The performance of DMFC with a non-equipotent serpentine flow field is compared to that with the equipotent serpentine flow field. And the performance of DMFCs placed in the horizontal and vertical directions is compared. Results show that the power difference between the DMFC with the non-equipotent serpentine flow field and that with the equipotent serpentine flow field is enlarged with the increase of the fuel cell current. The absolute peak power of the DMFC with the non-equipotent serpentine flow field, placed in the horizontal direction, is about 33% higher than that with the equipotent serpentine flow field. It is also found that the performance of the DMFC with the equipotent serpentine flow field is improved significantly while being placed in the horizontal direction as compared to that in the vertical direction. But the performances of the DMFC with the non-equipotent serpentine flow field are almost the same when it is placed in either directions.

Fuzzy Modeling and Optimization Based on Unit Commitment of a Power System Intergrated with Wind Power

Science & Technology Review. 2009, 27 (0920): 102-105. ;  doi:
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Abstract ( 539 )
With the drive of environmental protection and the trend of progressive exhaustion of traditional fossil energy sources, the interest is increased on integrating renewable energy sources into existing power systems. Among various renewable energy sources, wind energy is one of the most promising renewable energy sources. However, the intermittency and unpredictability of the wind power generation poses difficulty in control of frequency and scheduling of generation, which causes problems in the renewable-energy based hybrid power system. In views of this point, a fuzzy unit commitment model including wind farms is proposed. Primary energy emission and the risk are synthetically considered in the paper. Through defining the membership function, the deterministic problem is transformed into a fuzzy problem. Then it is reformulated into a nonlinear problem by means of the fuzzy satisfaction maximum-minimum. Genetic algorithm (GA) is used to solve this optimization problem. The simulation results of a 10 unit system demonstrate the feasibility of the proposed method. It can compromise the primary energy consumption with the risk according to the decision-maker's will. This paper provides some valuable information in both operation and planning in future.
Reviews

A Review on the Extraction and Property Analysis of Extracellular Polymeric Substance

Science & Technology Review. 2009, 27 (0920): 106-110. ;  doi:
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Abstract ( 911 )
Extracellular polymeric substance(EPS)has played an important role on the removal of pollutant in the wastewater for its special property, and has became one of the hottest research fields in the recent year. Based on the components, characteristics and properties of EPS, the research situation of the techniques on the EPS extraction, methods on the composition and property analysis were reviewed. The development trend and potential applications of EPS were also summarized. The paper would give some guide to the further studies and application on EPS.

Science & Technology Review. 2009, 27 (0920): 111-115. ;  doi:
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Abstract ( 1259 )
Brain injury could lead to hypoxie-ischemic in the brain. Ischemia in brain always results in hypoxia, however, hypoxia can occur without ischemia. A prolonged hypoxie-ischemic in brain tissue will cause abnormalities of material and energy metabolism in brain cells. Furthermore, the basic life activities will be affected, for instance, TCA, which generates adenosine triphosphate (ATP) and the ion transporting, would even stop working. The metabolism of proteins, nucleic acids and lipid are also affected. In a few minutes, the physiological function of the brain will be seriously affected. The longer time this situation continues, the more difficult it would be to reverse the process. Recent studies show that HBOT can improve the condition of hypoxie-ischemic in brain and it can repair and regenerate the cerebral tissue to some extent. The mechanism may be as follows: firstly, it would reduce the ET level, and alleviate spasticity of blood vessels, for better balance of the blood flow and lowering the intracranial pressure in the brain, improving the condition of the hypoxie-ischemic in the brain. Secondly, HBOT can protect the brain against cell injury by increasing MBP, and against cell apoptosis by changing the expressions of caspases gene family, Bcl-2/Bcl-xL and TSPO, moreover, it can speed the neuron regeneration by decreasing the Nogo-A/Ng-R. Thirdly, HBOT can increase the PLGF generation, and in turn, the generation of vascular and help repair the injured brain tissue. Lastly, HBOT may alter the expressions of several cytokines, which may alleviate the conditions of brain injury patients. All of those may help the recovery of brain functions, including the cognitive, memory, communicative competence and mentality. These directly or indirectly show that HBOT is effective for treatment of the brain injury.

Science & Technology Review. 2009, 27 (0920): 116-116. ;  doi:
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Abstract ( 483 )
Focus

Science & Technology Review. 2009, 27 (0920): 118-119. ;  doi:
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Abstract ( 492 )
科技评论

Science & Technology Review. 2009, 27 (0920): 120-120. ;  doi:
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Science & Technology Review. 2009, 27 (0920): 121-121. ;  doi:
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Abstract ( 491 )

Science & Technology Review. 2009, 27 (0920): 123-123. ;  doi:
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Abstract ( 476 )
主编心语

Science & Technology Review. 2009, 27 (0920): 125-125. ;  doi:
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Abstract ( 487 )
走向职场

Science & Technology Review. 2009, 27 (0920): 126-126. ;  doi:
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Abstract ( 472 )

Science & Technology Review. 2009, 27 (0920): 127-127. ;  doi:
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Science & Technology Review. 2009, 27 (0920): 128-132. ;  doi:
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Abstract ( 454 )

Science & Technology Review. 2009, 27 (0920): 133-137. ;  doi:
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Abstract ( 451 )

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