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   Science & Technology Review
2010, Vol.28, No. 07
13 April 2010

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Insisting on Strategic Orientation of Science Funds Development and Constantly Strengthening Service for the Construction of Innovative Country

Science & Technology Review. 2010, 28 (07): 2-3. ;  doi:
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Abstract ( 408 )
特别栏目

Science & Technology Review. 2010, 28 (07): 8-8. ;  doi:
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Science & Technology Review. 2010, 28 (07): 8-8. ;  doi:
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Science & Technology Review. 2010, 28 (07): 10-10. ;  doi:
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Science & Technology Review. 2010, 28 (07): 12-13. ;  doi:
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Science & Technology Review. 2010, 28 (07): 14-15. ;  doi:
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Science & Technology Review. 2010, 28 (07): 16-17. ;  doi:
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Science & Technology Review. 2010, 28 (07): 125-125. ;  doi:
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Science & Technology Review. 2010, 28 (07): 138-138. ;  doi:
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Science & Technology Review. 2010, 28 (07): 139-139. ;  doi:
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Abstract ( 333 )
半月科技风云

Science & Technology Review. 2010, 28 (07): 9-9. ;  doi:
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Abstract ( 417 )
科技事件

Science & Technology Review. 2010, 28 (07): 11-11. ;  doi:
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Abstract ( 382 )
科技工作者建议

Science & Technology Review. 2010, 28 (07): 18-18. ;  doi:
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Abstract ( 496 )
Articles

Progress in Experiment Researches on RE211 Single Crystal Whiskers

Science & Technology Review. 2010, 28 (07): 19-21. ;  doi:
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Abstract ( 488 )
In the resultant phase of peritectic decomposition of the RE123 (REBa2Cu3O7-δ), RE211(RE2BaCuO5) plays an important role in the construction of RE123 bulk, thin film, and coated conductor. In RE123 bulks, the boundary defects between RE211 particles and RE123 grains serve as strong flux pinning and thus help to increase the critical current density(Jc). In RE123 thin films, the influencing factors of formation of RE211 inclusions are important for obtaining high quality RE123 thin film. In the fabrication of coated conductor, second-phase Y211 particles of nanometer size were introduced by growth of alternating multilayer of ultra thin Y211 and Y123. Such a structure greatly enhances the Jc under a high magnetic field. As RE211 greatly influences the RE123 fabrication and its superconductive property, the growth of RE211 and the growth of large size Sm211 single crystal whiskers are a very important. In this paper, the experimental studies on RE211 single crystal whisker are reviewed, including also large size Sm211 single crystal whiskers(length over 15.5mm) growth by melt-method in single crystal stove.

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Science & Technology Review. 2010, 28 (07): 22-27. ;  doi:
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Abstract ( 521 )
The global climate is getting warmer during the 20th century, which has caused a great concern. This study analyzes the relationship and the changing rhythm of ground temperatures at depths of 0.8, 1.6 and 3.2m and the corresponding air temperature during 1954—2006 in Beijing. From the climate change rates, it is shown that the ground temperature and the air temperature are increased in the 51 years, with the increasing rates of 0.05, 0.18, 0.08℃/10a in the 0.8, 1.6, 3.2m for the ground temperature and 0.25℃/10a for the air temperature, and the increasing range is increased in recent years. The wavelet analysis shows a multiple periodic changing trend of either 10 or 15 years, and the temperature saw mutations in the beginning of the 1970's and the end of the 1980's. Before the 1970's, it is in the climatic warm period; during 1972 and 1989, it is in the climate cold period; in the years from 1990 to 2006, it is again in the climate warm period. And based on the results, it is expected that the next 15 or 16 years will see colder climate. But the general trend in the large scale is on the warmer side. Based on the standard established by World Meteorological Organization, the climate abnormal year is determined. The climate abnormal warm year with respect to the ground temperature is around 1963 and 2000, and the climate abnormal cold year is around 1957 and 1970. The abnormal cold year with respect to the air temperature has not been found, but the abnormal warm year is the year of 2006. The results provide a new angle to study the climate change in Beijing.

Contrast and Analysis of Two Severe Convective Weather Processes in June 2009

Science & Technology Review. 2010, 28 (07): 28-31. ;  doi:
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Abstract ( 525 )
Based on the data of mesoscale weather stations and the radar mosaic, the gales in two typical strong convection weather processes in June, 2009 are analyzed. The data come from the mesoscale experiment base of the key laboratory of Anhui Province. One process occurs on June 3-4, and the other process on June 14. The horizontal features and the characteristics of Doppler radar mosaic are studied. The two weather processes are compared. The results are as follows. (1) The 8~10 level gale number in the first severe convection process is less than that in the second process. The gales in the first process appear mostly in areas along Huai River and Northern Huai River. The gales in the second process appear mostly in areas of Anhui Province. The distribution range of the second process is much bigger than the first process. (2) The wind speed in the first process has a peak value, and in the second process has 2 peak values in the north area. (3) The first process is mainly created by radar echo once, and the second process is created by radar echo twice. The first process has one echo mergence phenomenon, and the second process has two echo mergence phenomena. The convective cell is enhanced after the mergence. Motion direction of the two processes is the same, that is, east by south. The intensity of the maximum radar echo is more than 55dBz.

Association of Cervical Disease Pathogenesis of Uighur and Han Women with the Loss of Estrogen Receptor 1 (ESR1) Protein Expression

Science & Technology Review. 2010, 28 (07): 32-36. ;  doi:
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Abstract ( 550 )
Previous reports show a hypermethylation of estrogen receptor 1 (ESR1) gene promoter in cervical carcinoma and it was suggested that this may lead to down regulation of gene expression or gene silencing. This paper studies the association of ESR1 loss at the protein level with the cervical disease pathogenesis, and its relation to ethnic differences between Uighur and Han women. A total of 180 cases of formalin fixed and paraffin-embedded cervical tissue specimens were collected from Uighur and Han women with cervicitis, cervical intraepithelial neoplasia (CIN) I/II/III and cervical squamous cell carcinoma, and the ESR1 protein expression was detected by immunohistochemistry. Experimental results show that ESR1 protein is ubiquitously expressed in both epithelial and stroma cells of the uterine cervix, but gradually lost in epithelial cells with the development of CIN and cervical squamous cell carcinoma. The loss rate of ESR1 protein expression is relatively low in the group of cervicitis and CIN I, is markedly increased in the group of CIN II/III (64%), to reach the highest level in cervical carcinoma (76%), and the difference is significant among groups (P<0.01), but no statistical difference in ages of the individuals (P>0.05); the alteration trend of the loss rate of ESR1 is common to women from both Uighur and Han ethnic groups, and the difference between two ethnic groups is also not statistically significant (P>0.05). These results indicate that the loss of ESR1 expression may be an early prediction marker of cervical squamous cell carcinoma, which may serve as an important evidence for revealing epigenetic mechanisms related to the hypermethylation of this gene.

Expression of HBME-1, Galectin-3 and CD44v6 in Follicular Thyroid Carcinoma and Atypical Adenoma

Science & Technology Review. 2010, 28 (07): 37-40. ;  doi:
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Abstract ( 502 )
his paper studies the immunohistochemical expressions of HBME-1, Galectin-3 and CD44v6 in Follicular Thyroid Carcinoma(FTC) and Atypical Thyroid Adenoma(ATA), in order to find out useful markers for their clinicopathological diagnosis and pathogenesis. SP immunohistochemical technique was applied to detect the expressions of HBME-1, Galectin-3 and CD44v6 in 37 FTC and 18 ATA. 10 cases of oncocytic thyroid adenoma(OTA), 8 cases of general follicular adenoma(FTA), and 7 cases of papillar thyroid carcinoma(PTC) were considered, together with 5 cases of normal thyroid from autopsy as the control group. Results show that the expressions of HBME-1, Galectin-3 and CD44v6 were 70.3%, 64.9%, 62.2% in FTC, 66.7%,61.1%,61.1% in ATA, respectively. These three markers do not have difference of statistical significance in FTC and ATA( χ2 and P values were 0.074 and 0.786, 0.094 and 0.759, 0.245 and 0.62, respectively). In the control group, the expressions of HBME-1, Galectin-3 and CD44v6 were all positive in OTA, 3/8, 6/8, 4/8 in FTA, 7/7, 6/7, 7/7 in PTC and negative in 5 normal thyroid. It is concluded that there is no statistical significance of HBME-1, Galectin-3 and CD44v6 in the diagnosis and differential diagnosis of FTC and ATA, and it should pay more attention to follow up these three markers. More studies are required on the diagnosis and differential diagnosis of FTC and ATA

The Reclamation and Ecological Effects of Arbuscular Mycorrhiza on Subsided Land in Shendong Coal Mine Areas

Science & Technology Review. 2010, 28 (07): 41-44. ;  doi:
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Abstract ( 593 )
It takes special technologies to apply arbuscular mycorrhiza fungi to the land reclamation. This paper studies sunflower growth, soil properties remediation and microbe population fluctuation after arbuscular mycorrhizal fungi being inoculated on the Shendong coal mine subsided land for 5 months. The following results are obtained. Arbuscular mycorrhizal fungi can shift the plant flowering period two weeks earlier than the control group. After 5 months growth, the mycorrhizal inoculation rate and the hyphal density are both increased. Mycorrhiza can promote plant growth. The leaf number and the weight of the mycorrhizal plants are increased as compared with the control group. The mycorrhizal plant root extends well. Mycorrhizal plant's dry weight is higher than the control group. The sunflowers' productions are also increased. The effectiveness of phosphorus and potassium is increased in the mycorrhizosphere soil. The populations of the microorganism are increased. All those show that their ecological effects are significantly improved. Arbuscular mycorrhizae would promote reclamated soil properties that will help the rehabilitation and sustainability of the ecological systems. These results provide a theoretical base for the micro-reclamation application in the coal mine areas, also for the reclamation practice.

The Relationship Between Soil Microorganism and Soil Fertility in the Process of Transforming Kangping′s Desertification

Science & Technology Review. 2010, 28 (07): 45-49. ;  doi:
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Abstract ( 1134 )
Soil microorganism plays a key role in the materail cycle an energy flow in soil ecological system. Sample of soils was selected, in order to know that the trend of soil microorganism commuity and quantity change, which were gathered from Haizhou, kangping county of Liaoning province. Compared difference in various vegetations and their growth state of the amount of soil microoganism. Exploration in the sand soil fertility management of the quality of response and the evolution of the law, in order to seek the best in the region provide the basis for fixing vegetation. The results show, in the main changes the trend of the soil microorganism quantity, that: in fixed sand dune is highest, and that of the moving sand dune is lowest, the semi-fixed sand dune between the fixed sand dune and the moving sand dune. Various types of microorganisms, in the distribution of different types of sand, has the proportion of different. Arrangement of the three the total number of microbial was different: the number of bacteria was more, followed by actinomycetes and fungi was least. In different enviroment and in different zones of the semi-fixed dunes were not the sane as the ratio between the composition of microbial taxa and various groups. The number of vegetation′s microorganisms were Joe than shrubs and herbaceous. The different of vegetation growth zones in the same proportion of microbial composition was different.

The Relationship Between the Plant Disposition and the Reduction of Nitrogen and Phosphorus in the Riparian Ecological Construction of Taohua River in Chongqing

Science & Technology Review. 2010, 28 (07): 50-54. ;  doi:
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Abstract ( 1308 )
In order to study the relationship between the plant disposition and the reduction of nitrogen and phosphorus in the riparian ecological construction of Taohua river in Chongqing, the field test, pot experiment and phosphorus adsorption isotherm experiment were carried out. The results show that the different plant dispositions have different effects on the reduction of nitrogen and phosphorus; the combination of Iris japonisa, Reineckia carnea and Cinnamomum camphora enjoys higher efficiency for removing particle-bound nitrogen and phosphorus; the higher the tree coverage, the lower the efficiency will be; the pot has no significant effect on the removal of NO-3 (nitrate), but has effect on the removal of PO3-4 (phosphate), and the pot with plants can prevent the loss of NO-3 ; the soil water content and the PO3-4 removal efficiency are anti-related; the loam phosphorus adsorption capacity is higher than that of the sand, with that of the Reineckia carnea being the highest, followed by that of Iris japonisa; the combination of Iris japonisa, Reineckia carnea, Gardenia Ellis var fortuniana and Cinnamomum camphora should be adopted in Taohua river, with the Iris japonisa being put above the Reineckia carnea, and Gardenia Ellis var fortuniana, Cinnamomum camphora being mixed planted with Reineckia carnea.

Ecological Features of Phytoplankton Community in Aweitan Reservoir in Xinjiang

Science & Technology Review. 2010, 28 (07): 55-58. ;  doi:
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Abstract ( 1316 )
Aweitan reservoir is located in Altay, Xinjiang. The water of the reservoir comes from a river at the head waters of Ertix River. It is an important water resource for fishery. The study of phytoplankton community structure in Aweitan reservoir was carried out on July 2008, October 2008 and May 2009 to explore the features related to fishery. A total of 99 species, belonging to 8 phylums were identified, including 8 dominant species, such as, Chroococcus minor, Cyllotella bodanica, Synedra acus, Planktosphaeria gelotinosa, Tetra?dron tumidulum, Scenedesmus quadricauda as well as Chlorella vulgaris. The Cyanophyta is accounted for 44% of the collectivity, and the Bacillariophyta for 35%. The cell density was the greatest (6.88±1.07×106ind/L) in the normal water season, and was the smallest in the wet season (0.97±0.23×106ind/L). The phytoplankton composition, cell density, and diversity were found to be closely related to the temperature and the water volume of Aweitan reservoir.

The Adsorption Mechanism of Bacillus cereus SY with respect to Cd

Science & Technology Review. 2010, 28 (07): 59-62. ;  doi:
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Abstract ( 435 )
A bacterial strain, named as SY, with strong cadmium resistance, is isolated from cadmium-contaminated soil in Zhangshi, Shenyang development zone. According to its morphological and biochemical characteristics and 16SrDNA sequence analysis, it is identified as Bacillus cereus. In the adsorption process of cadmium by SY, a large number of intracellular K+, Na+, Mg2+ and Ca2+, are released from the cells simultaneously. At the same time, the desorption rate of cadmium by SY changes with pH values. Using scanning electron microscopy, the cell micro-morphology is observed before and after adsorption of cadmium by SY. Using energy spectra, the cadmium elemental content changes are analyzed. And using IR spectrum, the changes in functional groups are analyzed in the cell surface. The results show that the surface of SY after adsorption of cadmium is linked up into a single stretch. The characteristic absorption band position, intensity and width see a certain change, while the base of the functional group on the cell surface remains unchanged. Therefore, the role of electrical adsorption,ion exchange and surface complexation are the most important factors in the process of adsorption of cadmium by SY. Mechanism of the absorption provides a theoretical basis for the biological adsorption of heavy metal method used in actual production.

Optimization of Protease Production Fermentation Conditions by Bacillus subtilis

Science & Technology Review. 2010, 28 (07): 63-67. ;  doi:
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Abstract ( 519 )
The response surface methodology (RSM) was used to optimize the immersion fermentation conditions for protease production by Bacillus subtilis. Firstly, dextrin and cornmeal were screened out as the most suitable carbon and nitrogen sources by using single factor experiment. Based on these, the assay Plackett-Burman was designed to evaluate relative factors related to protease production and three statistically significant factors (dextrin, cornmeal and yeast extract) were selected. And then the steepest ascent method was applied to define the optimal response region for these three factors, the RSM was used to optimize the above critical factors, and to find out the optimal concentration levels and the relationships between these factors. By solving the quadratic regression model equation by using appropriate statistic methods, the optimal fermentation concentrations were determined, with dextrin of 11.568g/L, cornmeal of 22.462g/L, yeast extract of 10.202g/L, NaCl of 5g/L, initial pH of 7.0, and 37℃ incubation for 48h. Protease activity after optimization was increased from 2463.95U/mL to 3281.79U/mL, an increase by 33.19%. The experiment data under various conditions have validated the theoretical values.

The Climatic Zoning and Variety Zoning of Grapevine in Gansu Province

Science & Technology Review. 2010, 28 (07): 68-72. ;  doi:
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Abstract ( 1184 )
Gansu Province is subdivided into 9 climate areas in this paper, based on the climatic zoning system proposed by Li Hua, et al, according to the climatic data of general weather stations in Gansu Province during 20 years. In the climatic zoning system, the frost-free period is used as the first index, the dryness index as the second index, and the level of earth burial to keep warm as the third index. Hexi Corridor, the center area of the Baiyin and the countryside of Lanzhou are shown to be the most suitable viticulture zones. Other areas see some unfavorable conditions such as overabundance of moisture in harvest-time, hence, are defined as the ordinary viticulture areas. In other special areas or small areas, high quality wine production also can be expected, a further subdivision is needed. By the comparison of three grapevine variety zoning indexes: Index of Huglin (IH), LTI and the effective active accumulated temperature, considering the actual situation of the viticulture in Gansu Province, the IH in grape growing season is found to be appropriate for variety zoning. And the suitable viticulture varieties are determined for each area through the results.

Influencing Factors of Nonlinear Flow Well Test Model in ASP Compounded Flooding Reservoir

Science & Technology Review. 2010, 28 (07): 77-82. ;  doi:
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Abstract ( 1185 )
The oil industry shows a great deal of interest in Alkali-Surfactant-Polymer(ASP) flooding in recovery operations. For its application, it is necessary to study the mechanisms of non-Newtonian flow through porous media. The present investigation shows that ASP solutions exhibit power-law and elastic properties within certain shear rates. The effect of viscoelasticity on the well test curve is studied from macroscopic perspective. Based on a varying cross-section throat model, the established viscous-elastic constitutive equation, with the consideration of the viscoelasticity and the variation of rheological parameters of ASP solutions, the seepage well test model of alkaline-surfactant-polymer solutions is established and solved by finite difference method, to obtain dimensional and dimensionless well test curves. From the dimensional typical curve, the effect of the parameters on the dimensional well test curve can be seen, such as the power-law exponent, injective rate, consistency coefficient, permeability, relaxation time, and tortuosity factor. The influence of these parameters can also be seen on the configuration of the well test curve in ASP reservoir. It is shown that it is necessary to consider the variation of rheological parameters and viscous-elasticity to some extent, in the application of the well test analysis method for ASP flooding reservoir. However, the power-law well test model is appropriate for ASP reservoir under the condition that rheological parameters change gently and with relatively small viscoelasticity. The research results of the well test model provide some food of thought for further investigation into ASP seepages.

The Reservoir Forming Conditions for Natural Gas in Paleogene Formation, Bonan Sag

Science & Technology Review. 2010, 28 (07): 83-87. ;  doi:
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Abstract ( 486 )
The prospect of natural gas exploration in Paleogene, Bonan sag is very promising. The study on the gas reservoir forming conditions will help to understand the forming process and the mechanism of the gas reservoirs, and to provide a theoretical basis for future gas exploration. It is carried out in this paper, based on geological, seismic and logging data in this area. It is shown that the main gas generating bed is the upper Sha4, with high thermal evolution degree, as a late accumulation, and with advantageous gas source conditions. All kinds of fans and secondary pores create favorable reservoir conditions of Eogene. Mudstone in middle and lower Sha3, together with salt bed and mudstone in upper Sha4, form a favorable regional cap bed and reservoir bed. The effective configuration of reservoir-forming and geologic conditions is the key factor of the natural gas accumulation. Deep Bonan sag correspondingly forms an inter and below salt bed natural gas reservoir-forming system. The gas generation center and the areas surrounding all kinds of fans are the next exploration targets.

Analysis of NMR Moveable Fluid Parameters in Ultra-low Permeability Glutenite Reservoir

Science & Technology Review. 2010, 28 (07): 88-90. ;  doi:
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Abstract ( 500 )
The movable fluid testing was carried out in 38 glutenite cores of ultra-low permeability reservoir using nuclear magnetic resonance technique. These cores are from Tenger III and Arxan formations of Uliastai Oilfield. Testing results were compared with cores of general sandstone reservoirs, and the correlations with the percentage parameter of moveable fluid and permeability and oil-displacement efficiency were analyzed. Ultra-low permeability glutenite reservoir is shown to have a low content of moveable fluid and strong heterogeneity. The characteristics of NMR are different in some extent from those of general ultra-low permeability sandstone reservoirs, with more mono peaks and a larger value of cutoff T2. The percentage parameter of moveable fluid is related to formation permeability to some degree, and the relation becomes better as the permeability increases. The average content of moveable fluid increases as the permeability increases for different formations. The oil-displacement efficiency becomes higher with increase of the percentage parameter of moveable fluid. Low content of moveable fluid is the major factor which negatively affects the exploitation of ultra-low permeability formation. The percentage parameter of moveable fluid can be used to predict the result of exploitation of ultra-low permeability formation.

A Robust Regression Model and Its Application in Calculating Shear Strength of Rock

Science & Technology Review. 2010, 28 (07): 91-95. ;  doi:
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Abstract ( 1298 )
There are two problems in the graphic method and the Least Quares(LS) method in determining the shear strength of rock. (1) The experimental data should be highly correlated, and separate data and anomalous data are not suitable. (2) The effect of anomalous values in test data is markedly shown because of the quadratic sum of residual errors in the least squares method. This paper proposes a shear strength parameter(Robust) regression analysis method. This method can be applied to analyze experimental data with poor correlation, and with anomalous values, and the effects of discrete and abnormal positioning can be weakened to improve the robustness and reliability of estimated parameters. In order to reduce the effect of anomalous values in the test data, the sum of residual absolute value is used instead of the quadratic sum of residual errors in the robust regression method, then the quadratic terms of anomalous value could be avoided, and the effect of anomalous values could be reduced. It is shown that the results of the two methods are the same when the test data is good, but the results of the robust regression method are better than those obtained by the least squares method when there are anomalous values in the test data.

Bending Strength of the Nano-silica Doped Flyash Sandwich Block

Science & Technology Review. 2010, 28 (07): 96-99. ;  doi:
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Abstract ( 579 )
In this paper, a new self thermal insulation mural material is proposed. Its major components include nanometer SiO2, portland cement and fly ash. It is made by mixing shrinkage-reducing agent, filling waste polystyrene in the hole, and natural curing. It is called the nano-silica doped flyash sandwich block. Based on the design requirements and standards of ordinary fly ash concrete hollow block, the corresponding size of the block, the size and distribution of the holes for this material are determined. The influences of major-factors such as fly ash, nanometer material, portland cement and water on the strength of the block are studied. The bending strength is the most important. Four factors and three levels for the orthogonal experiment are selected to optimize the matching ratio of the block. The result is 40% of fly ash, 14% of the portland cement, 0.5% of nanometer SiO2 and 22% of the water ash ratio. Such block features high bending strength and low cost. The bending strength and the compressive strength reach the same factor level combination as being reached in previous studies, but with higher ratio of bending strength to compressive strength. The block made by such matching ratio has a higher compressive strength and a higher flexural strength. The masonry made by such block can better withstand complex stresses.

The Effect of Elecromagnetic Field on the Solidification Structure of AZ80 Mg Alloy

Science & Technology Review. 2010, 28 (07): 100-103. ;  doi:
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Abstract ( 532 )
The ingot of AZ80 magnesium alloy was sawed into sheets of 8mm in thickness, then cut into strips of 120mm long and 5mm wide. Applying different electromagnetic fields, AZ80 magnesium alloy strips were heated to 660℃ in the resistance furnace. The influence of electromagnetic fields on the solidification structure of the AZ80 Mg alloy was examined. It is found that the grain becomes finer and the size and amount of inclusions are reduced in the sample with the AC magnetic field compared to the sample without the magnetic field. The grain sees no significant change in the DC magnetic field. The electron microprobe analysis shows that the Al and Zn contents inside the grain are increased.

The Effect of Compositions of Domestic Coal on the Performance of ESP and an Evaluation of ESP Adaptability

Science & Technology Review. 2010, 28 (07): 104-109. ;  doi:
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Abstract ( 764 )
The compositions of 122 types of domestic coal and fly ash samples are analyzed, to see the influence of coal and fly ash compositions on the performance of electrostatic precipitator. An evaluation method for the performance of ESP for domestic coal is proposed. The ESP adaptability for domestic coal is analyzed. It is shown that the compositions of coal and fly ash with respect to Sar, Na2O, Fe2O3, Al2O3 and SiO2 have a great influence on the performance of electrostatic precipitator. Sar, Na2O and Fe2O3 play a beneficial role in dust removal performance, while Al2O3 and SiO2 play a negative role. The effect on the performance of electrostatic precipitator is the result of the combined action of coal dust and fly ash compositions. For high-sulphur coal, Sar plays a leading role in the performance of electrostatic precipitator. For low-sulphur coal, the effect of Sar on the performance is relatively weakened, which mainly depends on the content of alkaline oxides in fly ash, content of water in flue gas and flue gas temperature. For 97.54% of the coals used in China, ESP can be used as the dust control device. With enhanced emission standard today, ESP still has a wide range of adaptability for domestic coal. The performance of the electrostatic precipitator in a few coal-fired power plants in China can not meet the requirements. The main reason for this is not due to the adaptability of the electrostatic precipitator, but due to the alteration of coal or the weakness of electric fields or small number of SCA.
Reviews

Progress in R&D on Solar Thermochemical Conversion

Science & Technology Review. 2010, 28 (07): 110-105. ;  doi:
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Abstract ( 645 )
This paper reviews the recent developments of studies of thermochemical conversion of concentrated solar thermal energy to chemical energy. The conversion has the advantage of producing long term storable energy carriers from solar energy and enables solar energy transportation from the sunbelt to remote population centers. The thermochemical conversion pathway is characterized by a theoretical high efficiency. However, there are special features in solar processes in comparison to conventional thermochemical processes-high thermal flux density and frequent thermal transients because of the fluctuating and intermittent insolation-and conventional industrial thermochemical processes are generally not suitable for solar driven processes. Therefore, the adaptation to such features of solar thermochemical processes has been an important R&D task in this research field. Thermochemical steam or CO2 gasification of coal, steam or CO2 reforming of methane, and splitting of fossil fuel, are industrially important endothermic processes to produce useful chemical fuels such as hydrogen, synthesis gas and C2-hydrocarbons, which have been considered as solar thermochemical processes. The technical difficulties and potential to conduct these endothermic processes by utilizing concentrated solar radiation as the process heat are recommended here. A low temperature solar thermochemical power plant with inherent CO2 recovery using methanol-fueled chemical-looping combustion is also given.
Focus

Science & Technology Review. 2010, 28 (07): 116-116. ;  doi:
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Science & Technology Review. 2010, 28 (07): 118-119. ;  doi:
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科技评论

Science & Technology Review. 2010, 28 (07): 117-117. ;  doi:
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Science & Technology Review. 2010, 28 (07): 120-120. ;  doi:
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Science & Technology Review. 2010, 28 (07): 123-123. ;  doi:
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