[Objective] This study aimed to investigate the optimal extraction process and antitumor effect of polysaccharides from Hemerocallis fulva. [Method] The con- tent of polysaccharides was determined with phenoFsulfuric ...[Objective] This study aimed to investigate the optimal extraction process and antitumor effect of polysaccharides from Hemerocallis fulva. [Method] The con- tent of polysaccharides was determined with phenoFsulfuric acid method. On the basis of single-factor experiment, an L9 (34) orthogonal design was performed with extraction rate of polysaccharides as an indicator to analyze the effects of solid-liq- uid ratio, extraction temperature, extraction time and extraction frequency on polysaccharide extraction and to investigate the optimal extraction process. Kunming mice were injected subcutaneously with sarcoma S180 ceils in the right axilla and in- tragastrically administrated with different doses of polysaccharides to observe antitu- mor rate. The levels of IL-2 and TNF-α in serum of S180 sarcoma-bearing mice were detected by antibody sandwich enzyme-linked inununosorbent assay (ELISA). [Result] The optimal extraction process of polysaccharides from H. fulva was: solid-liq- uid ratio of 1:25 (g/ml), extraction temperature of 80 ℃, extraction time of 2 h, and extraction frequency of three times. Under the optimized conditions, average extrac- tion rate of polysaccharides from H. fulva reached 17.47%. Polysacchandes extract-. ed from H. fulva could inhibit the growth of S180 sarcoma in mice. Antitumor rate in high-dose polysaccharide group (1,60 g/kg) reached 38.54%. The levels of IL-2 and ]NF-a in serum of S180 sarcoma-bearing mice were improved by polysaccharides. [Conclusion] Polysaccharides extracted from H. fulva exhibited strong antitumor activ- ity in vivo, which might be related with the improving effect of polysaccharides on immune function.展开更多
The Aronia melanocarpa El oit was used as test material. The microstruc-ture of normal and vitrified shoots and the characteristics of their stomas on leaf surface were compared by paraffin section and leaf epidermis-...The Aronia melanocarpa El oit was used as test material. The microstruc-ture of normal and vitrified shoots and the characteristics of their stomas on leaf surface were compared by paraffin section and leaf epidermis-tearing method. The results showed the palisade tissue of Aronia melanocarpa El oit consists of 2-3 lay-ers of cells. The stomas on lower epidermis cave in, and are smal and dense. There are abundant vessels and sieve tubes in stems. ln contrast, the main veins of vitrified shoots are unobvious, messy and irregular. The boundary between pal-isade tissue and spongy tissue is not obvious. The stomas open circularly and bigly. The stems are swel ing and thick, but the pith parenchyma cells are broken.展开更多
The number concentrations in the radius range of 0.06 – 5 μm of aerosol particles and meteorological parameters were measured on board during a cruise in the South China Sea from August 25 to October 12, 2012. Effec...The number concentrations in the radius range of 0.06 – 5 μm of aerosol particles and meteorological parameters were measured on board during a cruise in the South China Sea from August 25 to October 12, 2012. Effective fluxes in the reference height of 10 m were estimated by steady state dry deposition method based on the observed data, and the influences of different air masses on flux were discussed in this paper. The number size distribution was characterized by a bimodal mode, with the average total number concentration of(1.50 ± 0.76)×10~3 cm^(-3). The two mode radii were 0.099 μm and 0.886 μm, both of which were within the scope of accumulation mode. A typical daily average size distribution was compared with that measured in the Bay of Bengal. In the whole radius range, the number concentrations were in agreement with each other; the modes were more distinct in this study than that abtained in the Bay of Bengal. The size distribution of the fluxes was fitted with the sum of log-normal and power-law distribution. The impact of different air masses was mainly on flux magnitude, rather than the shape of spectral distribution. A semiempirical source function that is applicable in the radius range of 0.06 μm展开更多
Fuzzy analysis method for orthogonal test was used to study the effect of different sowing depth, seed soaking time, illumination intensity and culture soil on the seed germination rate of Eurya chinensis. The results...Fuzzy analysis method for orthogonal test was used to study the effect of different sowing depth, seed soaking time, illumination intensity and culture soil on the seed germination rate of Eurya chinensis. The results showed that the effect of seed soaking time on the sowing and seedling of Eurya chinensis was the biggest, and the ethers were illumination intensity, sowing depth and culture soil. The germi- nation rate was the highest when composite soil was used as culture soil and seeds were soaked for 48 h and sowed in topsoil, and a layer of sunshade net was used.展开更多
In this paper,the liquid seed medium of Grifola frondosa was optimized by single factor and orthogonal experiments using the shake flask culture method.The single factor experiments results showed that soybean powder ...In this paper,the liquid seed medium of Grifola frondosa was optimized by single factor and orthogonal experiments using the shake flask culture method.The single factor experiments results showed that soybean powder and maltose were the optimal nitrogen and carbon sources,and MgSO4 was the optimal inorganic salt.The orthogonal experiment results showed that the optimal combination of liquid seed culture medium for Grifola frondosa was:20%potato,0.75%soybean powder,5%maltose,0.1%KH2PO4,0.05%MgSO4,0.001%VB1.Using the optimized medium,shaking culture for 10 d under the inoculum amount of 5%,the temperature of 28℃,and the rotation speed of 150 r/min,the dry weight of mycelium exceeded 1.3228 g/100mL.展开更多
The breakdown voltage of long air-gaps in high-voltage transmission systems depends on not only the waveform of the applied voltage, but also the atmospheric conditions. Based on the results of the research project on...The breakdown voltage of long air-gaps in high-voltage transmission systems depends on not only the waveform of the applied voltage, but also the atmospheric conditions. Based on the results of the research project on the minimum air clearance for 800-kV HVDC substations at high altitudes, and also on the monthly and yearly statistics of the atmospheric data of last ten years and the altitude correction of the atmospheric data of last ten years, the altitude correction of the air-gaps for the 800-kV DC system under plan, 500-kV AC system to be built, and 1000-kV AC system under plan in the Inner Mongolia Plateau and the Yungui Plateau in China were studied with parameter G method. Correction factors for switching and lightning impulses were calculatod and then compared with those achieved according to IEC 71. It is shown that IEC 71 is appropriate for damp regions, and correction factors differ between plateau regions in China because of different atmospheric conditions.展开更多
[Objective] This study aimed to investigate the optimal condition for extrac- tion of ellagic acid from pomegranate peels. [Method] With ellagic acid yield as an indicator, ultrasound extraction method was adopted to ...[Objective] This study aimed to investigate the optimal condition for extrac- tion of ellagic acid from pomegranate peels. [Method] With ellagic acid yield as an indicator, ultrasound extraction method was adopted to extract the ellagic acid from pomegranate peels, and the concentration of ellagic acid was measured by using ul- traviolet spectrophotometry; L9(34) orthogonal experiment was designed with four fac- tors at three levels, to investigate the effect of extraction temperature, extraction du- ration, solid-liquid ratio and ultrasound power on extraction rate of ellagic acid. [Re- sult] The optimal extraction condition for ellagic acid is extraction temperature of 30 ~C, solid-liquid ratio of 1:200, extraction duration of 20 min, and ultrasound power of 50 W. The relationship between primary and secondary factors affecting experimental indicators was solid-liquid ratio 〉 extraction duration 〉 ultrasound power 〉 extraction temperature. [Conclusion] Solid-liquid ratio has the maximum effect on extraction rate of ellagic acid. The ellagic acid extraction technology identified in this study is rea- sonable and feasible.展开更多
Studies have reported that biochar is a sustainable amendment that improves the chemical and physical properties of soil.In this study,an incubation experiment was conducted to investigate the effects of different app...Studies have reported that biochar is a sustainable amendment that improves the chemical and physical properties of soil.In this study,an incubation experiment was conducted to investigate the effects of different application rates of biochar on the cracking pattern and shrinkage characteristics of lime concretion black soil after three wetting and drying cycles.Biochar derived from the corn straw and peanut shell mixture was applied to the soil at rates of 0,50,100,and 150 g kg^(-1)dry weight,representing the treatments T_(0),T_(50),T_(100),and T_(150),respectively.During the wetting and drying cycles,the cracking pattern and shrinkage characteristics of the unamended and amended soil samples were recorded.Application of biochar significantly increased soil organic carbon content in the samples.During soil desiccation,biochar significantly reduced the rate of water loss.Cracks propagated slowly and stopped due to the relatively higher water content in the soil applied with biochar.The cracking area density(ρ_c),equivalent width,fractal dimension,and cracking connectivity index decreased during the drying process with increasing application rate of biochar.Theρ_(c )value of the T_(50),T_(100),and T_(150) treatments decreased by 33.6%,52.1%,and 56.9%,respectively,after three wetting and drying cycles,whereas the T_(0) treatment exhibited a marginal change.The coefficient of linear extensibility,an index used to describe onedimentional shrinkage,of the unamended soil sample(T_(0))was approximately 0.23.Application of 100 and 150 g kg^(-1)biochar to the soil significantly reduced the shrinkage capacity by 41.45%and 45.54%,respectively.The slope of the shrinkage characteristics curve,which indicates the ralationship between soil void ratio and moisture ratio,decreased with increase in the application rate of biochar.Furthermore,compared with the T_(0) treatment,the proportional shrinkage zone of the shrinkage characteristic curve of the T_(50),T_(100),and T_(150) treatments decreased by 5.8%,13.1%,and 12.1%,respectively.Differences were not observed in the moisture ratio at the maximum curvature of the shrinkage characteristic curve among the treatments.The results indicate that biochar can alter the cracking pattern and shrinkage characteristics of lime concretion black soil.However,the effects of biochar on the shrinkage of lime concretion black soil are dependent on the number of wetting and drying cycles.展开更多
Application of organic waste to saline alkaline soils is considered to be a good practice for soil remediation. The effects of applying different organic amendments (e.g., cattle dung, vermicompost, biofertilizer) a...Application of organic waste to saline alkaline soils is considered to be a good practice for soil remediation. The effects of applying different organic amendments (e.g., cattle dung, vermicompost, biofertilizer) and earthworm inoculations (Eisenia fetida) on saline soils and cotton growth were investigated during i year of cotton cultivation. Compared to the control (applied with inorganic NPK fertilizer), applying organic amendments improved soil physicochemical properties. Biofertilizer application improved available nutrient content, reduced short-term soil electrical conductivity, and produced the highest cotton yield, whereas cattle dung and vermicompost applications resulted in higher soil organic matter content. Application of organic amendments significantly increased soil microbial biomass carbon during the flowering period, which sharply declined at harvest. This was especially true for the biofertilizer treatment, which also exhibited lower nematode abundance compared with the other organic materials. Earthworm inoculation following cattle dung application failed to significantly change soil physicochemical properties when compared to the treatments without earthworm inoculation. Results suggest that biofertilizer application to saline soil would improve soil nutrient status in the short-term, whereas cattle dung application would improve soil organic matter content and increase soil organism abundance to a greater extent. However, different strategies might be required for long-term saline soil remediation.展开更多
Large eddy simulation(LES)is used to calculate the in-cylinder turbulent flow field in a direct injection spark ignition(DISI)engine.The computations are carried out for three different maximum valve lifts(MVL)and thr...Large eddy simulation(LES)is used to calculate the in-cylinder turbulent flow field in a direct injection spark ignition(DISI)engine.The computations are carried out for three different maximum valve lifts(MVL)and throughout 100 consecutive engine cycles.The simulated results as well as corresponding particle image velocimetry(PIV)measurement database are analyzed by the proper orthogonal decomposition(POD)method.Through a new developed POD quadruple decomposition the instantaneous in-cylinder flow fields are decomposed into four parts,named mean field,coherent field,transition field and turbulent field,respectively.Then the in-cylinder turbulent flow characteristics and cycle-to-cycle variations(CCV)are studied separately upon the four part flow fields.Results indicate that each part exhibits its specific characteristics and has close connection with others.The mean part contains more than 50%of the total kinetic energy and the energy cascade phenomenon occurs among the four part fields;the coherent field part possesses the highest CCV level which dominates CCV of the bulk flow.In addition,it is observed that a change in MVL affects significantly the in-cylinder flow behavior including CCV,especially for the coherent part.Furthermore,the POD analysis demonstrates that at least 25 sample cycles for the mean velocity and 50 sample cycles for the RMS velocity are necessary for obtaining converged and correct results in CCV.展开更多
Fast neutron tomography has been established as an inspection and detection tool at the NECTAR facility at the FRM-II reac- tor. Scattered neutrons from the object become a major disturbance and bring in artifacts and...Fast neutron tomography has been established as an inspection and detection tool at the NECTAR facility at the FRM-II reac- tor. Scattered neutrons from the object become a major disturbance and bring in artifacts and deviations in reconstruction re- suits, especially for hydrogenous material object. In this article, an iterative scattering correction method for fast neutron to- mography was proposed. In each loop of iteration the scattering component of the projections will be simulated by Mon- te-Carlo program MCNPX based on the previous reconstruction result and then it will be subtracted from original projections. The differences between scattering components at different perspectives were quantitatively evaluated and an average scatter- ing component image was used for all projections finally. Smooth and uniform slices with more clear edges were obtained and the new reconstructed attenuation coefficients are quite close to the real one compared to the results without scattering correc- tion, in which case the relative error of the reconstructed attenuation coefficients is about 10%-30%.展开更多
文摘[Objective] This study aimed to investigate the optimal extraction process and antitumor effect of polysaccharides from Hemerocallis fulva. [Method] The con- tent of polysaccharides was determined with phenoFsulfuric acid method. On the basis of single-factor experiment, an L9 (34) orthogonal design was performed with extraction rate of polysaccharides as an indicator to analyze the effects of solid-liq- uid ratio, extraction temperature, extraction time and extraction frequency on polysaccharide extraction and to investigate the optimal extraction process. Kunming mice were injected subcutaneously with sarcoma S180 ceils in the right axilla and in- tragastrically administrated with different doses of polysaccharides to observe antitu- mor rate. The levels of IL-2 and TNF-α in serum of S180 sarcoma-bearing mice were detected by antibody sandwich enzyme-linked inununosorbent assay (ELISA). [Result] The optimal extraction process of polysaccharides from H. fulva was: solid-liq- uid ratio of 1:25 (g/ml), extraction temperature of 80 ℃, extraction time of 2 h, and extraction frequency of three times. Under the optimized conditions, average extrac- tion rate of polysaccharides from H. fulva reached 17.47%. Polysacchandes extract-. ed from H. fulva could inhibit the growth of S180 sarcoma in mice. Antitumor rate in high-dose polysaccharide group (1,60 g/kg) reached 38.54%. The levels of IL-2 and ]NF-a in serum of S180 sarcoma-bearing mice were improved by polysaccharides. [Conclusion] Polysaccharides extracted from H. fulva exhibited strong antitumor activ- ity in vivo, which might be related with the improving effect of polysaccharides on immune function.
文摘The Aronia melanocarpa El oit was used as test material. The microstruc-ture of normal and vitrified shoots and the characteristics of their stomas on leaf surface were compared by paraffin section and leaf epidermis-tearing method. The results showed the palisade tissue of Aronia melanocarpa El oit consists of 2-3 lay-ers of cells. The stomas on lower epidermis cave in, and are smal and dense. There are abundant vessels and sieve tubes in stems. ln contrast, the main veins of vitrified shoots are unobvious, messy and irregular. The boundary between pal-isade tissue and spongy tissue is not obvious. The stomas open circularly and bigly. The stems are swel ing and thick, but the pith parenchyma cells are broken.
基金supported by the National Natural Science Foundation of China under Grant NO.41276009
文摘The number concentrations in the radius range of 0.06 – 5 μm of aerosol particles and meteorological parameters were measured on board during a cruise in the South China Sea from August 25 to October 12, 2012. Effective fluxes in the reference height of 10 m were estimated by steady state dry deposition method based on the observed data, and the influences of different air masses on flux were discussed in this paper. The number size distribution was characterized by a bimodal mode, with the average total number concentration of(1.50 ± 0.76)×10~3 cm^(-3). The two mode radii were 0.099 μm and 0.886 μm, both of which were within the scope of accumulation mode. A typical daily average size distribution was compared with that measured in the Bay of Bengal. In the whole radius range, the number concentrations were in agreement with each other; the modes were more distinct in this study than that abtained in the Bay of Bengal. The size distribution of the fluxes was fitted with the sum of log-normal and power-law distribution. The impact of different air masses was mainly on flux magnitude, rather than the shape of spectral distribution. A semiempirical source function that is applicable in the radius range of 0.06 μm
基金Supported by Project of Forestry Science and Technology Plan of Guangdong Province(2005-15)~~
文摘Fuzzy analysis method for orthogonal test was used to study the effect of different sowing depth, seed soaking time, illumination intensity and culture soil on the seed germination rate of Eurya chinensis. The results showed that the effect of seed soaking time on the sowing and seedling of Eurya chinensis was the biggest, and the ethers were illumination intensity, sowing depth and culture soil. The germi- nation rate was the highest when composite soil was used as culture soil and seeds were soaked for 48 h and sowed in topsoil, and a layer of sunshade net was used.
文摘In this paper,the liquid seed medium of Grifola frondosa was optimized by single factor and orthogonal experiments using the shake flask culture method.The single factor experiments results showed that soybean powder and maltose were the optimal nitrogen and carbon sources,and MgSO4 was the optimal inorganic salt.The orthogonal experiment results showed that the optimal combination of liquid seed culture medium for Grifola frondosa was:20%potato,0.75%soybean powder,5%maltose,0.1%KH2PO4,0.05%MgSO4,0.001%VB1.Using the optimized medium,shaking culture for 10 d under the inoculum amount of 5%,the temperature of 28℃,and the rotation speed of 150 r/min,the dry weight of mycelium exceeded 1.3228 g/100mL.
文摘The breakdown voltage of long air-gaps in high-voltage transmission systems depends on not only the waveform of the applied voltage, but also the atmospheric conditions. Based on the results of the research project on the minimum air clearance for 800-kV HVDC substations at high altitudes, and also on the monthly and yearly statistics of the atmospheric data of last ten years and the altitude correction of the atmospheric data of last ten years, the altitude correction of the air-gaps for the 800-kV DC system under plan, 500-kV AC system to be built, and 1000-kV AC system under plan in the Inner Mongolia Plateau and the Yungui Plateau in China were studied with parameter G method. Correction factors for switching and lightning impulses were calculatod and then compared with those achieved according to IEC 71. It is shown that IEC 71 is appropriate for damp regions, and correction factors differ between plateau regions in China because of different atmospheric conditions.
基金Supported by College-level Special Fund of Sichuan Agricultural University(06070904)~~
文摘[Objective] This study aimed to investigate the optimal condition for extrac- tion of ellagic acid from pomegranate peels. [Method] With ellagic acid yield as an indicator, ultrasound extraction method was adopted to extract the ellagic acid from pomegranate peels, and the concentration of ellagic acid was measured by using ul- traviolet spectrophotometry; L9(34) orthogonal experiment was designed with four fac- tors at three levels, to investigate the effect of extraction temperature, extraction du- ration, solid-liquid ratio and ultrasound power on extraction rate of ellagic acid. [Re- sult] The optimal extraction condition for ellagic acid is extraction temperature of 30 ~C, solid-liquid ratio of 1:200, extraction duration of 20 min, and ultrasound power of 50 W. The relationship between primary and secondary factors affecting experimental indicators was solid-liquid ratio 〉 extraction duration 〉 ultrasound power 〉 extraction temperature. [Conclusion] Solid-liquid ratio has the maximum effect on extraction rate of ellagic acid. The ellagic acid extraction technology identified in this study is rea- sonable and feasible.
基金supported by the National Key Research and Development Project of China (No. 2016YFD0300801)the National Science and Technology Support Project of China (No. 2012BAD05B00)
文摘Studies have reported that biochar is a sustainable amendment that improves the chemical and physical properties of soil.In this study,an incubation experiment was conducted to investigate the effects of different application rates of biochar on the cracking pattern and shrinkage characteristics of lime concretion black soil after three wetting and drying cycles.Biochar derived from the corn straw and peanut shell mixture was applied to the soil at rates of 0,50,100,and 150 g kg^(-1)dry weight,representing the treatments T_(0),T_(50),T_(100),and T_(150),respectively.During the wetting and drying cycles,the cracking pattern and shrinkage characteristics of the unamended and amended soil samples were recorded.Application of biochar significantly increased soil organic carbon content in the samples.During soil desiccation,biochar significantly reduced the rate of water loss.Cracks propagated slowly and stopped due to the relatively higher water content in the soil applied with biochar.The cracking area density(ρ_c),equivalent width,fractal dimension,and cracking connectivity index decreased during the drying process with increasing application rate of biochar.Theρ_(c )value of the T_(50),T_(100),and T_(150) treatments decreased by 33.6%,52.1%,and 56.9%,respectively,after three wetting and drying cycles,whereas the T_(0) treatment exhibited a marginal change.The coefficient of linear extensibility,an index used to describe onedimentional shrinkage,of the unamended soil sample(T_(0))was approximately 0.23.Application of 100 and 150 g kg^(-1)biochar to the soil significantly reduced the shrinkage capacity by 41.45%and 45.54%,respectively.The slope of the shrinkage characteristics curve,which indicates the ralationship between soil void ratio and moisture ratio,decreased with increase in the application rate of biochar.Furthermore,compared with the T_(0) treatment,the proportional shrinkage zone of the shrinkage characteristic curve of the T_(50),T_(100),and T_(150) treatments decreased by 5.8%,13.1%,and 12.1%,respectively.Differences were not observed in the moisture ratio at the maximum curvature of the shrinkage characteristic curve among the treatments.The results indicate that biochar can alter the cracking pattern and shrinkage characteristics of lime concretion black soil.However,the effects of biochar on the shrinkage of lime concretion black soil are dependent on the number of wetting and drying cycles.
基金supported by the National Natural Science Foundation of China (No. 41371305)the National Key Research and Development Program of China (No. 2017YFD0202000)
文摘Application of organic waste to saline alkaline soils is considered to be a good practice for soil remediation. The effects of applying different organic amendments (e.g., cattle dung, vermicompost, biofertilizer) and earthworm inoculations (Eisenia fetida) on saline soils and cotton growth were investigated during i year of cotton cultivation. Compared to the control (applied with inorganic NPK fertilizer), applying organic amendments improved soil physicochemical properties. Biofertilizer application improved available nutrient content, reduced short-term soil electrical conductivity, and produced the highest cotton yield, whereas cattle dung and vermicompost applications resulted in higher soil organic matter content. Application of organic amendments significantly increased soil microbial biomass carbon during the flowering period, which sharply declined at harvest. This was especially true for the biofertilizer treatment, which also exhibited lower nematode abundance compared with the other organic materials. Earthworm inoculation following cattle dung application failed to significantly change soil physicochemical properties when compared to the treatments without earthworm inoculation. Results suggest that biofertilizer application to saline soil would improve soil nutrient status in the short-term, whereas cattle dung application would improve soil organic matter content and increase soil organism abundance to a greater extent. However, different strategies might be required for long-term saline soil remediation.
基金supported by the National Natural Science Foundation of China(Grant Nos.51176020 and 51376029)
文摘Large eddy simulation(LES)is used to calculate the in-cylinder turbulent flow field in a direct injection spark ignition(DISI)engine.The computations are carried out for three different maximum valve lifts(MVL)and throughout 100 consecutive engine cycles.The simulated results as well as corresponding particle image velocimetry(PIV)measurement database are analyzed by the proper orthogonal decomposition(POD)method.Through a new developed POD quadruple decomposition the instantaneous in-cylinder flow fields are decomposed into four parts,named mean field,coherent field,transition field and turbulent field,respectively.Then the in-cylinder turbulent flow characteristics and cycle-to-cycle variations(CCV)are studied separately upon the four part flow fields.Results indicate that each part exhibits its specific characteristics and has close connection with others.The mean part contains more than 50%of the total kinetic energy and the energy cascade phenomenon occurs among the four part fields;the coherent field part possesses the highest CCV level which dominates CCV of the bulk flow.In addition,it is observed that a change in MVL affects significantly the in-cylinder flow behavior including CCV,especially for the coherent part.Furthermore,the POD analysis demonstrates that at least 25 sample cycles for the mean velocity and 50 sample cycles for the RMS velocity are necessary for obtaining converged and correct results in CCV.
基金supported by the Academic Exchange Fund of Peking University Graduate Schoolthe National Basic Research Program of China(Grant No.2010CB833106)
文摘Fast neutron tomography has been established as an inspection and detection tool at the NECTAR facility at the FRM-II reac- tor. Scattered neutrons from the object become a major disturbance and bring in artifacts and deviations in reconstruction re- suits, especially for hydrogenous material object. In this article, an iterative scattering correction method for fast neutron to- mography was proposed. In each loop of iteration the scattering component of the projections will be simulated by Mon- te-Carlo program MCNPX based on the previous reconstruction result and then it will be subtracted from original projections. The differences between scattering components at different perspectives were quantitatively evaluated and an average scatter- ing component image was used for all projections finally. Smooth and uniform slices with more clear edges were obtained and the new reconstructed attenuation coefficients are quite close to the real one compared to the results without scattering correc- tion, in which case the relative error of the reconstructed attenuation coefficients is about 10%-30%.