The three dimensional variable cross-section roll forming is a kind of new metal forming technol- ogy which combines large forming force, multi-axis linkage movement and space synergic movement, and the sequential syn...The three dimensional variable cross-section roll forming is a kind of new metal forming technol- ogy which combines large forming force, multi-axis linkage movement and space synergic movement, and the sequential synergic movement of the ganged roller group is used to complete the metal sheet forming according to the shape of the complicated and variable forming part data. The control system should meet the demands of quick response to the test requirements of the product part. A new kind of real time data driving multi-axis linkage and synergic movement control strategy of 3D roll forming is put forward in the paper. In the new control strategy, the forming data are automatically generated according to the shape of the parts, and the multi-axis linkage movement together with cooperative motion among the six stands of the 3D roll forming machine is driven by the real-time information, and the control nodes are also driven by the forming data. The new control strategy is applied to a 48 axis 3D roll forming machine developed by our research center, and the control servo period is less than 10ms. A forming experiment of variable cross section part is carried out, and the forming preci- sion is better than ＋ 0.5mm by the control strategy. The result of the experiment proves that the control strategy has significant potentiality for the development of 3D roll forming production line with large scale, multi-axis ganged and svner^ic movement展开更多
We present new data on the^(63)Cu(γ,n)cross-section studied using a quasi-monochromatic and energy-tunableγbeam produced at the Shanghai Laser Electron Gamma Source to resolve the long-standing discrepancy between e...We present new data on the^(63)Cu(γ,n)cross-section studied using a quasi-monochromatic and energy-tunableγbeam produced at the Shanghai Laser Electron Gamma Source to resolve the long-standing discrepancy between existing measurements and evaluations of this cross-section.Using an unfolding iteration method,^(63)Cu(γ,n)data were obtained with an uncertainty of less than 4%,and the inconsistencies between the available experimental data were discussed.Theγ-ray strength function of^(63)Cu(γ,n)was successfully extracted as an experimental constraint.We further calculated the cross-section of the radiative neutron capture reaction^(62)Cu(n,γ)using the TALYS code.Our calculation method enables the extraction of(n,γ)cross-sections for unstable nuclides.展开更多
A brand new and feasible method for measuring the carrier lifetime and capture cross-section of a barrier by using the negative resistance segment of the I-V characteristics of a barrier-type thyristor（BTH） is put f...A brand new and feasible method for measuring the carrier lifetime and capture cross-section of a barrier by using the negative resistance segment of the I-V characteristics of a barrier-type thyristor（BTH） is put forward.The measuring principle and calculation method are given.The BTH samples are experimentally measured and the results are analyzed in detail.展开更多
We consider the problem of population estimation using capture-recapture data, where capture probabilities can vary between sampling occasions and behavioural responses. The original model is not identifiable without ...We consider the problem of population estimation using capture-recapture data, where capture probabilities can vary between sampling occasions and behavioural responses. The original model is not identifiable without further restrictions. The novelty of this article is to expand the current research practice by developing a hierarchical Bayesian approach with the assumption that the odds of recapture bears a constant relationship to the odds of initial capture. A real-data example of deer mice population is given to illustrate the proposed method. Three simulation studies are developed to inspect the performance of the proposed Bayesian estimates. Compared with the maximum likelihood estimates discussed in Chao et al. (2000), the hierarchical Bayesian estimate provides reasonably better population estimation with less mean square error;moreover, it is sturdy to underline relationship between the initial and re-capture probabilities. The sensitivity study shows that the proposed Bayesian approach is robust to the choice of hyper-parameters. The third simulation study reveals that both relative bias and relative RMSE approach zero as population size increases. A R-package is developed and used in both data example and simulation.展开更多
The capture and fission analysis of heavy ion induced fusion reactions leading to the formation of Z=107-111 superheavy nuclei has been carried out.Attempts have been made to analyze the synthesis traits,such as excit...The capture and fission analysis of heavy ion induced fusion reactions leading to the formation of Z=107-111 superheavy nuclei has been carried out.Attempts have been made to analyze the synthesis traits,such as excitation functions,formation probabilities,barrier characteristics etc.The l-summed Wong model provides a decent description of available data on capture(σCap)and fusion-fission(σff)cross-sections and hence is exploited to make relevant predictions for future experiments.The capture and fusion-fission excitation functions are predicted for the least explored region of superheavy nuclei(SHN)i.e.Z=107-111.The role of massasymmetry(η),Coulomb factor(ZPZT)deformation and orientations,Businari-Gallone massasymmetry(αBG)fission barrier(Bf)etc is duly explored.The present study concludes that the mass-asymmetric reactions involving 24Mg,30Si,and 36S projectiles are preferred for the synthesis of unknown isotopes of Z=107-111.Alternatively,the doubly magic 48Ca-projectile also provides a competing alternative to produce neutron-rich isotopes of the abovementioned SHN.展开更多
The reaction cross-sections of^(238)U(n,γ)^(239)U have been experimentally determined at neutron energies of6.117±0.119 MeV,4.626±0.086 MeV,and 3.622±0.348 MeV employing the relative activation approac...The reaction cross-sections of^(238)U(n,γ)^(239)U have been experimentally determined at neutron energies of6.117±0.119 MeV,4.626±0.086 MeV,and 3.622±0.348 MeV employing the relative activation approach along with the off-line γ-ray spectroscopy method.The D(d,n)3He reaction was utilized to obtain monoenergetic neutrons of the required energy,and the^(197)Au(n,γ)^(198)Au reaction cross-sections were adopted as the referential standard to ascertain the neutron capture cross-sections of^(238)U.Furthermore,the effects of low-energy scattered neutrons,neutron fluence fluctuations,counting of geometric corrections when measuring γ-rays,and neutron and γ-ray self-absorption caused by the sample thickness have been considered and revised in the present work.For a comparison with experimental results,the cross-sections of the^(238)U(n,γ)^(239)U reaction were calculated theoretically with the original parametric TALYS-1.9 program.The experimental measurements were in contrast to previous experimental re sults and the evaluation data available for ROSFOND-2010,CENDL-3.2 and ENDF/B-VIII.0.展开更多
CaO-based sorbent is considered to be a promising candidate for capturing CO_2 at high temperature. However,the adsorption capacity of CaO decreases sharply with the increase of the carbonation/calcination cycles. In ...CaO-based sorbent is considered to be a promising candidate for capturing CO_2 at high temperature. However,the adsorption capacity of CaO decreases sharply with the increase of the carbonation/calcination cycles. In this study, CaO was derived from calcium acetate(CaAc_2), which was doped with different elements(Mg, Al,Ce, Zr and La) to improve the cyclic stability. The carbonation conversion and cyclic stability of sorbents were tested by thermogravimetric analyzer(TGA). The sorbents were characterized by N_2 isothermal adsorption measurements, scanning electron microscopy(SEM) and X-ray diffraction(XRD). The results showed that the cyclic stabilities of all modified sorbents were improved by doping elements, while the carbonation conversions of sorbents in the 1st cycle were not increased by doping different elements. After 22 cycles, the cyclic stabilities of CaO–Al, CaO–Ce and CaO–La were above 96.2%. After 110 cycles, the cyclic stability of CaO–Al was still as high as 87.1%. Furthermore, the carbonation conversion was closely related to the critical time and specific surface area.展开更多
提升绳是矿井、电梯等系统的关键承载部件,其安全性至关重要。针对传统检测方法实时性差、误报率高的问题,构建了基于图像识别的提升绳缺陷识别-定位-联动系统。该系统通过结构先验设定ROI(Region of Interest,感兴趣区域),采用多尺度...提升绳是矿井、电梯等系统的关键承载部件,其安全性至关重要。针对传统检测方法实时性差、误报率高的问题,构建了基于图像识别的提升绳缺陷识别-定位-联动系统。该系统通过结构先验设定ROI(Region of Interest,感兴趣区域),采用多尺度融合模型提升识别精度,结合绳体几何映射与时序跟踪实现动态捕捉与稳定复核,并在控制层实现分级联动。现场验证表明,该系统识别准确率高、误报率低,具备良好的工程适应性。展开更多
Although various strategies have been proposed for enrichment of circulating tumor cells(CTCs),the clinical outcomes of CTC detection are far from satisfactory.The prevailingmethodologies for CTC detection are general...Although various strategies have been proposed for enrichment of circulating tumor cells(CTCs),the clinical outcomes of CTC detection are far from satisfactory.The prevailingmethodologies for CTC detection are generally oriented towardnaturallyoccurring targets;however,misdetection and interference are prevalent due to the diverse phenotypes and subpopulations of CTCs,which are highly heterogeneous.Here,a CTC isolation system based on the“labelcapture-release”process is demonstrated for the precise and highly efficient enrichment of CTCs fromclinical blood samples.On the basis of the abnormal glycometabolism of tumor cells,the surface of CTCs can be decorated with artificial azido groups.By utilizing bio-orthogonal plates designed with dibenzocyclooctane(DBCO)and disulfide groups,withthe aid of anti-fouling effects,CTCs labeled with azido groups can be captured through a copper-free click reaction and subsequently released via disulfide reduction.The technique has been shown to label tumor cells with the epithelial cell adhesion molecule(EpCAM)+and EpCAM~phenotypes in both adherent and suspended states.Moreover,it effectively isolates all epithelial,interstitial,and hybrid phenotypes of CTCs from clinical blood samples collected from dozens of patients across more than 10 cancer types.Compared to the clinically approved CTC detection system,our strategy demonstrates superior performance from the perspective of broad-spectrum and accurate recognition of heterogeneous CTCs.More importantly,most of the captured CTCs can be released with the retention of living activity,making this technique well suited for downstream applications such as drug susceptibility tests involving viable CTCs.展开更多
基金Supported by National Key Technology R&D Program(No.2011BAG03B03)
文摘The three dimensional variable cross-section roll forming is a kind of new metal forming technol- ogy which combines large forming force, multi-axis linkage movement and space synergic movement, and the sequential synergic movement of the ganged roller group is used to complete the metal sheet forming according to the shape of the complicated and variable forming part data. The control system should meet the demands of quick response to the test requirements of the product part. A new kind of real time data driving multi-axis linkage and synergic movement control strategy of 3D roll forming is put forward in the paper. In the new control strategy, the forming data are automatically generated according to the shape of the parts, and the multi-axis linkage movement together with cooperative motion among the six stands of the 3D roll forming machine is driven by the real-time information, and the control nodes are also driven by the forming data. The new control strategy is applied to a 48 axis 3D roll forming machine developed by our research center, and the control servo period is less than 10ms. A forming experiment of variable cross section part is carried out, and the forming preci- sion is better than ＋ 0.5mm by the control strategy. The result of the experiment proves that the control strategy has significant potentiality for the development of 3D roll forming production line with large scale, multi-axis ganged and svner^ic movement
基金supported by the National Key Research and Development Program(Nos.2023YFA1606901 and 2022YFA1602400)National Natural Science Foundation of China(Nos.U2230133,12275338,and 12388102)Open Fund of the CIAE Key Laboratory of Nuclear Data(No.JCKY2022201C152).
文摘We present new data on the^(63)Cu(γ,n)cross-section studied using a quasi-monochromatic and energy-tunableγbeam produced at the Shanghai Laser Electron Gamma Source to resolve the long-standing discrepancy between existing measurements and evaluations of this cross-section.Using an unfolding iteration method,^(63)Cu(γ,n)data were obtained with an uncertainty of less than 4%,and the inconsistencies between the available experimental data were discussed.Theγ-ray strength function of^(63)Cu(γ,n)was successfully extracted as an experimental constraint.We further calculated the cross-section of the radiative neutron capture reaction^(62)Cu(n,γ)using the TALYS code.Our calculation method enables the extraction of(n,γ)cross-sections for unstable nuclides.
文摘A brand new and feasible method for measuring the carrier lifetime and capture cross-section of a barrier by using the negative resistance segment of the I-V characteristics of a barrier-type thyristor（BTH） is put forward.The measuring principle and calculation method are given.The BTH samples are experimentally measured and the results are analyzed in detail.
文摘We consider the problem of population estimation using capture-recapture data, where capture probabilities can vary between sampling occasions and behavioural responses. The original model is not identifiable without further restrictions. The novelty of this article is to expand the current research practice by developing a hierarchical Bayesian approach with the assumption that the odds of recapture bears a constant relationship to the odds of initial capture. A real-data example of deer mice population is given to illustrate the proposed method. Three simulation studies are developed to inspect the performance of the proposed Bayesian estimates. Compared with the maximum likelihood estimates discussed in Chao et al. (2000), the hierarchical Bayesian estimate provides reasonably better population estimation with less mean square error;moreover, it is sturdy to underline relationship between the initial and re-capture probabilities. The sensitivity study shows that the proposed Bayesian approach is robust to the choice of hyper-parameters. The third simulation study reveals that both relative bias and relative RMSE approach zero as population size increases. A R-package is developed and used in both data example and simulation.
基金financial support from the UGC-DAE Consortium for Scientific Research,F.No.UGC-DAE-CSR-KC/CRS/19/NP09/0920the INSPIRE-fellowship(grant no.DST/INSPIRE/03/2015/000199).
文摘The capture and fission analysis of heavy ion induced fusion reactions leading to the formation of Z=107-111 superheavy nuclei has been carried out.Attempts have been made to analyze the synthesis traits,such as excitation functions,formation probabilities,barrier characteristics etc.The l-summed Wong model provides a decent description of available data on capture(σCap)and fusion-fission(σff)cross-sections and hence is exploited to make relevant predictions for future experiments.The capture and fusion-fission excitation functions are predicted for the least explored region of superheavy nuclei(SHN)i.e.Z=107-111.The role of massasymmetry(η),Coulomb factor(ZPZT)deformation and orientations,Businari-Gallone massasymmetry(αBG)fission barrier(Bf)etc is duly explored.The present study concludes that the mass-asymmetric reactions involving 24Mg,30Si,and 36S projectiles are preferred for the synthesis of unknown isotopes of Z=107-111.Alternatively,the doubly magic 48Ca-projectile also provides a competing alternative to produce neutron-rich isotopes of the abovementioned SHN.
基金Supported by the Key Laboratory of Nuclear Data foundation (6142A08200104)。
文摘The reaction cross-sections of^(238)U(n,γ)^(239)U have been experimentally determined at neutron energies of6.117±0.119 MeV,4.626±0.086 MeV,and 3.622±0.348 MeV employing the relative activation approach along with the off-line γ-ray spectroscopy method.The D(d,n)3He reaction was utilized to obtain monoenergetic neutrons of the required energy,and the^(197)Au(n,γ)^(198)Au reaction cross-sections were adopted as the referential standard to ascertain the neutron capture cross-sections of^(238)U.Furthermore,the effects of low-energy scattered neutrons,neutron fluence fluctuations,counting of geometric corrections when measuring γ-rays,and neutron and γ-ray self-absorption caused by the sample thickness have been considered and revised in the present work.For a comparison with experimental results,the cross-sections of the^(238)U(n,γ)^(239)U reaction were calculated theoretically with the original parametric TALYS-1.9 program.The experimental measurements were in contrast to previous experimental re sults and the evaluation data available for ROSFOND-2010,CENDL-3.2 and ENDF/B-VIII.0.
基金Supported by Capture CO_2 and Storage Technology Jointly Studied by USA and China(2013DFB60140-04)Northwest University Graduate Innovative Talent Training Project(YZZ12036)
文摘CaO-based sorbent is considered to be a promising candidate for capturing CO_2 at high temperature. However,the adsorption capacity of CaO decreases sharply with the increase of the carbonation/calcination cycles. In this study, CaO was derived from calcium acetate(CaAc_2), which was doped with different elements(Mg, Al,Ce, Zr and La) to improve the cyclic stability. The carbonation conversion and cyclic stability of sorbents were tested by thermogravimetric analyzer(TGA). The sorbents were characterized by N_2 isothermal adsorption measurements, scanning electron microscopy(SEM) and X-ray diffraction(XRD). The results showed that the cyclic stabilities of all modified sorbents were improved by doping elements, while the carbonation conversions of sorbents in the 1st cycle were not increased by doping different elements. After 22 cycles, the cyclic stabilities of CaO–Al, CaO–Ce and CaO–La were above 96.2%. After 110 cycles, the cyclic stability of CaO–Al was still as high as 87.1%. Furthermore, the carbonation conversion was closely related to the critical time and specific surface area.
文摘提升绳是矿井、电梯等系统的关键承载部件,其安全性至关重要。针对传统检测方法实时性差、误报率高的问题,构建了基于图像识别的提升绳缺陷识别-定位-联动系统。该系统通过结构先验设定ROI(Region of Interest,感兴趣区域),采用多尺度融合模型提升识别精度,结合绳体几何映射与时序跟踪实现动态捕捉与稳定复核,并在控制层实现分级联动。现场验证表明,该系统识别准确率高、误报率低,具备良好的工程适应性。
基金supported by the National Key R&D Program of China(2021YFB3800800)the National Natural Science Foundation of China(81903057,82073284,32000962,82402491,and 82272157)+2 种基金Shenzhen Science and Technology Research Funding(JCYJ20200109115601720)the Hong Kong PDFS-RGC Postdoctoral Fellowship Scheme(PDFS2122-1S08 and CityU 9061014)Hong Kong HMRF(Health and Medical Research Fund)(2120972 and CityU 9211320)。
文摘Although various strategies have been proposed for enrichment of circulating tumor cells(CTCs),the clinical outcomes of CTC detection are far from satisfactory.The prevailingmethodologies for CTC detection are generally oriented towardnaturallyoccurring targets;however,misdetection and interference are prevalent due to the diverse phenotypes and subpopulations of CTCs,which are highly heterogeneous.Here,a CTC isolation system based on the“labelcapture-release”process is demonstrated for the precise and highly efficient enrichment of CTCs fromclinical blood samples.On the basis of the abnormal glycometabolism of tumor cells,the surface of CTCs can be decorated with artificial azido groups.By utilizing bio-orthogonal plates designed with dibenzocyclooctane(DBCO)and disulfide groups,withthe aid of anti-fouling effects,CTCs labeled with azido groups can be captured through a copper-free click reaction and subsequently released via disulfide reduction.The technique has been shown to label tumor cells with the epithelial cell adhesion molecule(EpCAM)+and EpCAM~phenotypes in both adherent and suspended states.Moreover,it effectively isolates all epithelial,interstitial,and hybrid phenotypes of CTCs from clinical blood samples collected from dozens of patients across more than 10 cancer types.Compared to the clinically approved CTC detection system,our strategy demonstrates superior performance from the perspective of broad-spectrum and accurate recognition of heterogeneous CTCs.More importantly,most of the captured CTCs can be released with the retention of living activity,making this technique well suited for downstream applications such as drug susceptibility tests involving viable CTCs.
