The automobile industry has been searching for vehicles that use less energy and emit fewer pollutants, which has resulted in a high demand for fuel-efficient vehicles. Because of their higher strength-to-weight ratio...The automobile industry has been searching for vehicles that use less energy and emit fewer pollutants, which has resulted in a high demand for fuel-efficient vehicles. Because of their higher strength-to-weight ratio compared to traditional steel, using fiber-reinforcement composite materials in automobile bodies has emerged as the most effective strategy for improving fuel efficiency while maintaining safety standards. This research paper examined the utilization of fiber-reinforced composite materials in car bodies to meet the increasing consumer demand for fuel-efficient and eco-friendly vehicles. It particularly focused on a carbon-aramid fiber-reinforced composite impact beam for passenger car side door impact protection. Despite the encouraging prospects of the carbon-aramid fiber-reinforced beam, the research uncovered substantial defects in the fabrication process, resulting in diminished load-bearing capacity and energy absorption. As a result, the beam was un-successful in three-point bending tests. This was accomplished by using an I cross-section design with varying thickness because of the higher area moment of inertia. Vacuum-assisted resin transfer molding (VARTM) manufacturing process was used and the finished beam underwent to three-point bending tests.展开更多
Radiation encephalopathy is the main complication of cranial radiotherapy. It can cause necrosis of brain tissue and cognitive dysfunction. Our previous work had proved that a natural antioxidant shikonin possessed pr...Radiation encephalopathy is the main complication of cranial radiotherapy. It can cause necrosis of brain tissue and cognitive dysfunction. Our previous work had proved that a natural antioxidant shikonin possessed protective effect on cerebral ischemic injury. Here we investigated the effects of shikonin on carbon ion beam induced radiation brain injury in mice. Pretreatment with shikonin significantly increased the SOD and CAT activities and the ratio of GSH/GSSG in mouse brain tissues compared with irradiated group （P〈0.01）, while obviously reduced the MDA and PCO contents and the RO$ levels derived from of the brain mitochondria.展开更多
In an attempt to elucidate the biological effects and underlying mutations involving flower color in ornamental plants following carbon ion beam radiation,shoots of geranium were exposed at dosages of 0,10,15,30,and40...In an attempt to elucidate the biological effects and underlying mutations involving flower color in ornamental plants following carbon ion beam radiation,shoots of geranium were exposed at dosages of 0,10,15,30,and40 Gy,and one flower color mutant was obtained.The morphological characteristics,physiological aspects,and DNA polymorphisms between wild-type and flower color mutants were analyzed.The colors of petal,peduncle,pistil,and stamen of the mutant displayed significant differences compared to those of the wild-type.Compared to the original plants,the total anthocyanin content in the petals of the mutant significantly decreased,resulting in a light pink petal phenotype.DNA polymorphisms detected by random amplified polymorphic DNA analysis showed that the ratio of different bands between the wild-type and mutant reached up to 13.2%.The present study demonstrates that carbon ion beam irradiation is effective in inducing genomic variations,resulting in flower color geranium mutants within a relatively short period of time.Meanwhile,the developed flower-color mutants may be potentially used in future mutational research studies involving ornamental plants.展开更多
The applications of carbon ion beam in tumor therapy have attracted more attention in recent years.Monte Carlo simulation is an important approach to obtain accurate radiotherapy parameters. In this work, a400 Me V/u ...The applications of carbon ion beam in tumor therapy have attracted more attention in recent years.Monte Carlo simulation is an important approach to obtain accurate radiotherapy parameters. In this work, a400 Me V/u carbon ion beam incident on water phantom was simulated with Gate/Geant4 tools. In methods, the authors set up a carbon ion beam source according to the experiment parameters of Haettner, defined the geometries and materials, set up the physics processes, and designed the means of information collection. In results,the authors obtained the longitudinal dose distribution, the lateral dose distribution, and the relative uncertainty of dose. The dose contributions of all kinds of fragments were calculated detailedly and compared with the Francis results. This work is helpful for people's understanding of the dose distributions produced by carbon ion beam and fragments in water. The simulation method is also significative for radiotherapy treatment planning of carbon ion beam, and it is easy to extend. For obtaining a special result, we may change the particle energy, particle type,target material, target geometry, physics process, detector,etc.展开更多
Based on the nonlocal continuum theory, the nonlinear vibration of an embedded single-walled carbon nanotube （SWCNT） subjected to a harmonic load is in- vestigated. In the present study, the SWCNT is assumed to be a...Based on the nonlocal continuum theory, the nonlinear vibration of an embedded single-walled carbon nanotube （SWCNT） subjected to a harmonic load is in- vestigated. In the present study, the SWCNT is assumed to be a curved beam, which is unlike previous similar work. Firstly, the governing equations of motion are derived by the Hamilton principle, meanwhile, the Galerkin approach is carried out to convert the nonlinear integral-differential equation into a second-order nonlinear ordinary differ- ential equation. Then, the precise integration method based on the local linearzation is appropriately designed for solving the above dynamic equations. Besides, the numerical example is presented, the effects of the nonlocal parameters, the elastic medium constants, the waviness ratios, and the material lengths on the dynamic response are analyzed. The results show that the above mentioned effects have influences on the dynamic behavior of the SWCNT.展开更多
A new approach using a low-energy electron beam radiation system was investigated to synthesize carbon hybrid structures in amorphous carbon thin films. Two types of amorphous carbon films, which were 15at% iron conta...A new approach using a low-energy electron beam radiation system was investigated to synthesize carbon hybrid structures in amorphous carbon thin films. Two types of amorphous carbon films, which were 15at% iron containing film and with column/inter-column structures, were deposited onto Si substrates by a sputtering technique and subsequently exposed to an electron shower of which the energy and dose rate were much smaller compared to an intense electron beam used in a transmission electron microscopy. As a result of the low-energy and low-dose electron irradiation process, graphitic structures formed in amorphous matrix at a relatively low temperature up to 450 K. Hybrid carbon thin films containing onion-like structures in an amorphous carbon matrix were synthesized by dynamic structural modification of iron containing amorphous carbon thin films. It was found that the graphitization progressed more in the electron irradiation than in annealing at 773 K, and it was attributed to thermal and catalytic effects which are strongly related to grain growth of metal clusters. On the other hand, a reversal of TEM image contrast was observed in a-C films with column/inter-column structures. It is presumed that preferable graphitization occurred in the inter-column regions induced by electron irradiation.展开更多
In order to see whether carbon ion (C-ion) beams have a biological advantage over X-rays, studies were designed to examine the effects of C-ion beams on radiosensitivity in X-ray resistant cells. Clinically relevant X...In order to see whether carbon ion (C-ion) beams have a biological advantage over X-rays, studies were designed to examine the effects of C-ion beams on radiosensitivity in X-ray resistant cells. Clinically relevant X-ray resistant SAS-R cells derived from human tongue cancer SAS cells were used. The cells were exposed to X-rays or Spread-Out Bragg peak (SOBP) beam C-ions. Cell survival was measured using a modified high-density survival assay. Cell survival signaling and cell death signaling were analyzed using flow cytometry. The cells were labeled with putative cancer stem cell markers such as CD44 and CD326. SAS-R cells were 1.6 times more radioresistant than SAS cells after exposure to X-rays. Cell survival was similar in each cell line after exposure to C-ion beams. SAS-R cells displayed enhanced cell survival signaling when compared to SAS cells under normal conditions. On the other hand, the phosphorylation of AKT-related proteins decreased and polycaspase activities were enhanced when cells were irradiated with C-ion beams in both cell lines. More CD44 and CD326 positive cells were seen in SAS-R cells than in SAS cells. Moreover, the marker positive cell numbers significantly decreased after exposure to C-ion beams when compared to X-rays at iso-survival doses in SAS-R cells. C-ion beams efficiently induced cell killing in X-ray resistant cells which displayed activated cell survival signaling and contained more numerous cancer stem-like cells.展开更多
Multi-walled carbon nanotubes were irradiated with 40 keV Si ion beam to a dose of 1×1017 cm-2. The multiple-way carbon nanowire junctions and the Si doping in carbon nanowires were realized. Moreover, the forma-...Multi-walled carbon nanotubes were irradiated with 40 keV Si ion beam to a dose of 1×1017 cm-2. The multiple-way carbon nanowire junctions and the Si doping in carbon nanowires were realized. Moreover, the forma- tion processes of carbon nanowire junctions and the corresponding mechanism were studied.展开更多
文摘The automobile industry has been searching for vehicles that use less energy and emit fewer pollutants, which has resulted in a high demand for fuel-efficient vehicles. Because of their higher strength-to-weight ratio compared to traditional steel, using fiber-reinforcement composite materials in automobile bodies has emerged as the most effective strategy for improving fuel efficiency while maintaining safety standards. This research paper examined the utilization of fiber-reinforced composite materials in car bodies to meet the increasing consumer demand for fuel-efficient and eco-friendly vehicles. It particularly focused on a carbon-aramid fiber-reinforced composite impact beam for passenger car side door impact protection. Despite the encouraging prospects of the carbon-aramid fiber-reinforced beam, the research uncovered substantial defects in the fabrication process, resulting in diminished load-bearing capacity and energy absorption. As a result, the beam was un-successful in three-point bending tests. This was accomplished by using an I cross-section design with varying thickness because of the higher area moment of inertia. Vacuum-assisted resin transfer molding (VARTM) manufacturing process was used and the finished beam underwent to three-point bending tests.
基金supported by Key Program of National Natural Science Foundation of China(U1432248)National Natural Science Foundation of China(11175222,11305226)
文摘Radiation encephalopathy is the main complication of cranial radiotherapy. It can cause necrosis of brain tissue and cognitive dysfunction. Our previous work had proved that a natural antioxidant shikonin possessed protective effect on cerebral ischemic injury. Here we investigated the effects of shikonin on carbon ion beam induced radiation brain injury in mice. Pretreatment with shikonin significantly increased the SOD and CAT activities and the ratio of GSH/GSSG in mouse brain tissues compared with irradiated group （P〈0.01）, while obviously reduced the MDA and PCO contents and the RO$ levels derived from of the brain mitochondria.
基金supported by the National Natural Science Foundation of China(Grant Nos.11205218,11275171,and 11405234)the Knowledge Innovation Project of the Chinese Academy of Sciences(CAS)(No.KJCX2-EW-N05)+1 种基金CAS‘‘Light of West China’’Program(No.29Y506020)the Youth Innovation Promotion Association of CAS(No.29Y506030)supported this study
文摘In an attempt to elucidate the biological effects and underlying mutations involving flower color in ornamental plants following carbon ion beam radiation,shoots of geranium were exposed at dosages of 0,10,15,30,and40 Gy,and one flower color mutant was obtained.The morphological characteristics,physiological aspects,and DNA polymorphisms between wild-type and flower color mutants were analyzed.The colors of petal,peduncle,pistil,and stamen of the mutant displayed significant differences compared to those of the wild-type.Compared to the original plants,the total anthocyanin content in the petals of the mutant significantly decreased,resulting in a light pink petal phenotype.DNA polymorphisms detected by random amplified polymorphic DNA analysis showed that the ratio of different bands between the wild-type and mutant reached up to 13.2%.The present study demonstrates that carbon ion beam irradiation is effective in inducing genomic variations,resulting in flower color geranium mutants within a relatively short period of time.Meanwhile,the developed flower-color mutants may be potentially used in future mutational research studies involving ornamental plants.
基金supported by the National Natural Science Foundation of China(No.H1809)
文摘The applications of carbon ion beam in tumor therapy have attracted more attention in recent years.Monte Carlo simulation is an important approach to obtain accurate radiotherapy parameters. In this work, a400 Me V/u carbon ion beam incident on water phantom was simulated with Gate/Geant4 tools. In methods, the authors set up a carbon ion beam source according to the experiment parameters of Haettner, defined the geometries and materials, set up the physics processes, and designed the means of information collection. In results,the authors obtained the longitudinal dose distribution, the lateral dose distribution, and the relative uncertainty of dose. The dose contributions of all kinds of fragments were calculated detailedly and compared with the Francis results. This work is helpful for people's understanding of the dose distributions produced by carbon ion beam and fragments in water. The simulation method is also significative for radiotherapy treatment planning of carbon ion beam, and it is easy to extend. For obtaining a special result, we may change the particle energy, particle type,target material, target geometry, physics process, detector,etc.
基金Project supported by the National Basic Research Program of China (No. 2011CB610300)the National Natural Science Foundation of China (Nos. 10972182, 11172239, and 10902089)+3 种基金the 111 Project of China (No. B07050)the Ph. D. Programs Foundation of Ministry of Education of China (No. 20106102110019)the Open Foundation of State Key Laboratory of Structural Analysis of Industrial Equipment (No. GZ0802)the Doctorate Foundation of Northwestern Polytechnical University (No. CX201224)
文摘Based on the nonlocal continuum theory, the nonlinear vibration of an embedded single-walled carbon nanotube （SWCNT） subjected to a harmonic load is in- vestigated. In the present study, the SWCNT is assumed to be a curved beam, which is unlike previous similar work. Firstly, the governing equations of motion are derived by the Hamilton principle, meanwhile, the Galerkin approach is carried out to convert the nonlinear integral-differential equation into a second-order nonlinear ordinary differ- ential equation. Then, the precise integration method based on the local linearzation is appropriately designed for solving the above dynamic equations. Besides, the numerical example is presented, the effects of the nonlocal parameters, the elastic medium constants, the waviness ratios, and the material lengths on the dynamic response are analyzed. The results show that the above mentioned effects have influences on the dynamic behavior of the SWCNT.
文摘A new approach using a low-energy electron beam radiation system was investigated to synthesize carbon hybrid structures in amorphous carbon thin films. Two types of amorphous carbon films, which were 15at% iron containing film and with column/inter-column structures, were deposited onto Si substrates by a sputtering technique and subsequently exposed to an electron shower of which the energy and dose rate were much smaller compared to an intense electron beam used in a transmission electron microscopy. As a result of the low-energy and low-dose electron irradiation process, graphitic structures formed in amorphous matrix at a relatively low temperature up to 450 K. Hybrid carbon thin films containing onion-like structures in an amorphous carbon matrix were synthesized by dynamic structural modification of iron containing amorphous carbon thin films. It was found that the graphitization progressed more in the electron irradiation than in annealing at 773 K, and it was attributed to thermal and catalytic effects which are strongly related to grain growth of metal clusters. On the other hand, a reversal of TEM image contrast was observed in a-C films with column/inter-column structures. It is presumed that preferable graphitization occurred in the inter-column regions induced by electron irradiation.
文摘In order to see whether carbon ion (C-ion) beams have a biological advantage over X-rays, studies were designed to examine the effects of C-ion beams on radiosensitivity in X-ray resistant cells. Clinically relevant X-ray resistant SAS-R cells derived from human tongue cancer SAS cells were used. The cells were exposed to X-rays or Spread-Out Bragg peak (SOBP) beam C-ions. Cell survival was measured using a modified high-density survival assay. Cell survival signaling and cell death signaling were analyzed using flow cytometry. The cells were labeled with putative cancer stem cell markers such as CD44 and CD326. SAS-R cells were 1.6 times more radioresistant than SAS cells after exposure to X-rays. Cell survival was similar in each cell line after exposure to C-ion beams. SAS-R cells displayed enhanced cell survival signaling when compared to SAS cells under normal conditions. On the other hand, the phosphorylation of AKT-related proteins decreased and polycaspase activities were enhanced when cells were irradiated with C-ion beams in both cell lines. More CD44 and CD326 positive cells were seen in SAS-R cells than in SAS cells. Moreover, the marker positive cell numbers significantly decreased after exposure to C-ion beams when compared to X-rays at iso-survival doses in SAS-R cells. C-ion beams efficiently induced cell killing in X-ray resistant cells which displayed activated cell survival signaling and contained more numerous cancer stem-like cells.
基金Supported by the National Natural Science Foundation of China (Grant No.10375085)the Chinese Academy of Sciences Knowledge Innovation Pro-gram (Grant No. KJCX3.SYW.N10).
文摘Multi-walled carbon nanotubes were irradiated with 40 keV Si ion beam to a dose of 1×1017 cm-2. The multiple-way carbon nanowire junctions and the Si doping in carbon nanowires were realized. Moreover, the forma- tion processes of carbon nanowire junctions and the corresponding mechanism were studied.
