在已有的投影后变分(variation after projection,VAP)方法的基础上,进一步考虑宇称投影。由此,VAP计算可将模型空间扩展至多个主大壳。考虑多个主大壳,VAP计算需要处理质心问题。对于质心修正,采用与标准壳模型完全一致的办法,将波函...在已有的投影后变分(variation after projection,VAP)方法的基础上,进一步考虑宇称投影。由此,VAP计算可将模型空间扩展至多个主大壳。考虑多个主大壳,VAP计算需要处理质心问题。对于质心修正,采用与标准壳模型完全一致的办法,将波函数的质心部分进行分离。在已有的VAP方法中,只能计算正宇称低激发态。采用新方法,在psd模型空间中计算了12 C的正负宇称低激发态。通过与壳模型(shell model,SM)精确值进行比较,无论正宇称态,还是负宇称态,都得到了非常好的近似结果。至此,VAP新方法可以计算壳模型中所有类型的低激发态。这是首次能够同时计算原子核正负宇称态的VAP计算。展开更多
With the development of mobile technology, especially the development of 3G and mobile IP, the computational capacity of handsets is becoming more and more powerful, which provides a new method to solve the difficulti...With the development of mobile technology, especially the development of 3G and mobile IP, the computational capacity of handsets is becoming more and more powerful, which provides a new method to solve the difficulties encountered in real time GIS accessing caused by the characteristics of mobility and remoteness of fieldwork in oilfield. On the basis of studying in-depth on the technologies of J2ME platform, Mobile SVG and mobile data transfer, etc., and in accordance with the actual situation of oilfield, the design framework of oilfield mobile GIS service is put forward and the schemes of key technologies are given in this paper, which establishes the technical foundation for the construction of “Digital Oilfield”.展开更多
Bamboo vascular bundle fiber and parenchyma(BP)are separated by high-temperature treatment with saturated steam.Bamboo vascular bundle fiber is widely used in the market,but how to develop and utilize parenchyma tissu...Bamboo vascular bundle fiber and parenchyma(BP)are separated by high-temperature treatment with saturated steam.Bamboo vascular bundle fiber is widely used in the market,but how to develop and utilize parenchyma tissue is a difficult problem.The sulfated cellulose nanofibers(ANFs)were obtained by sulfating BP with a deep eutectic solvent(DES),which provided a theoretical basis for the value-added utilization of BP.Using DES as the reaction medium and reagent,the BP was grafted with a sulfonic acid group to form a gel substance in water,ANFs and nanocellulose gel were obtained by ultrasonic cell crusher.The highest yield of ANFS was 75%.The width of the ANFs was about 3 nm,and a small number of nanofiber aggregates existed at the same time.A high aspect ratio of ANFs,due to their high viscosity,has potential applications as enhancers at low concen-trations.Lewis acid(ZnCl 2)added based on binary(DES)greatly improved the thermal stability of the ANFs and maintained the crystal form of cellulose I.展开更多
In this study,the effects of three different particle sizes of wood wastes(A=–8+12 mesh;B=–12+20 mesh;C=–20+30 mesh)and factory shavings(D)on the properties of particleboard were investigated.According to the test ...In this study,the effects of three different particle sizes of wood wastes(A=–8+12 mesh;B=–12+20 mesh;C=–20+30 mesh)and factory shavings(D)on the properties of particleboard were investigated.According to the test results,three-layer particleboard was designed.Particleboard face layers made with mixture of A,B,and C.The core layer made with D.The ratio of core layer to face layers is 50:50.Three-layer particleboard were fabricated with 12%urea-formaldehyde(UF)resins and three different high voltage electrostatic field intensities(0 kv,30 kv,60 kv).The internal bond(IB)strength,modulus of rupture(MOR),modulus of elasticity(MOE),thickness swelling(TS),and water absorption(WA)of particleboard were evaluated.The density distribution of the three-layer particleboard were examined by vertical density profiles(VDP),and the bonding mechanism and functional groups changes in the particles were analyzed by FTIR analysis.The results showed that HVEF treatment intensity play a remarkable role in properties of particleboard.The particleboard with higher electrostatic field intensities treatment has higher MOE,MOR,IB,and TS.Under HVEF treatment(60 kv),the MOR,modulus of MOE,and IB of three-layer particleboard were 23.61 N/mm^(2),2787.09 N/mm^(2),and 0.86 N/mm^(2),respectively.FTIR indicated that the surface activity of wood particles was increased electric field treatment.展开更多
To make a large area of dredger fill silt surface layer form working face and subsequent construction problems, the project conducts the bamboo network reinforcement in the silt surface layer. It makes the surface lay...To make a large area of dredger fill silt surface layer form working face and subsequent construction problems, the project conducts the bamboo network reinforcement in the silt surface layer. It makes the surface layer bearing capacity to meet the construction requirement of deep processing. Based on Shantou Municipal Road Embankment Treatment Engineering and the project, the bamboo network reinforcement technology to reinforce the dredger fill super soft soil surface layer is used. The results show that the bearing capacity of hydraulic fill super soft soil surface layer is 32.6 kPa after 3 months treatment. The surface layer bearing capacity after 3 months treatment improved 323% than the early treatment and increased 695% than no processing. The results indicate that the reinforcement effect is outstanding and provide the basis for drafting the dredger fill super soft soil surface layer treatment plan.展开更多
With the rapid development of mobile communication and computer network technologies, the new mobile learning mode has been accepted by more and more people. In this paper, taking the learning system under mobile envi...With the rapid development of mobile communication and computer network technologies, the new mobile learning mode has been accepted by more and more people. In this paper, taking the learning system under mobile environment and from the perspective of necessary theoretic knowledge and relative technologies for mobile learning, the structural frame of the mobile learning system was discussed and constructed. According to this structural frame, the learning system under mobile environment was designed and applied into the OS course.展开更多
Parvalbumin-positive retinal ganglion cells(PV+RGCs)are an essential subset of RGCs found in various species.However,their role in transmitting visual information remains unclear.Here,we characterized PV+RGCs in the r...Parvalbumin-positive retinal ganglion cells(PV+RGCs)are an essential subset of RGCs found in various species.However,their role in transmitting visual information remains unclear.Here,we characterized PV+RGCs in the retina and explored the functions of the PV+RGC-mediated visual pathway.By applying multiple viral tracing strategies,we investigated the downstream of PV+RGCs across the whole brain.Interestingly,we found that the PV+RGCs provided direct monosynaptic input to PV+excitatory neurons in the superficial layers of the superior colliculus(SC).Ablation or suppression of SC-projecting PV+RGCs abolished or severely impaired the flight response to looming visual stimuli in mice without affecting visual acuity.Furthermore,using transcriptome expression profiling of individual cells and immunofluorescence colocalization for RGCs,we found that PV+RGCs are predominant glutamatergic neurons.Thus,our findings indicate the critical role of PV+RGCs in an innate defensive response and suggest a non-canonical subcortical visual pathway from excitatory PV+RGCs to PV+SC neurons that regulates looming visual stimuli.These results provide a potential target for intervening and treating diseases related to this circuit,such as schizophrenia and autism.展开更多
Edible bird’s nest(EBN)is a kind of natural invigorant with a long history of consumption in Asia,especially in China.EBN is formed by mixing the saliva of swiftlets(Aerodramus)with feathers and other components duri...Edible bird’s nest(EBN)is a kind of natural invigorant with a long history of consumption in Asia,especially in China.EBN is formed by mixing the saliva of swiftlets(Aerodramus)with feathers and other components during the breeding season.Proteins are the most important nutrient in EBN.By studying proteins in EBN,we can not only elucidate their components at the molecular level,but also study their bioactivities.Therefore,it is of great significance to study the proteins in EBN.Previous research on the proteins in EBN was preliminary and cursory,and no one has summarized and analyzed the proteins in EBN and correlated the bioactivities of these proteins with the biological functions of EBN.This article focused on the proteins in EBN,listed the proteins identified in different proteomic studies,and introduced the sources,structures and bioactivities of the most frequently identified proteins,including acidic mammalian chitinase,lysyl oxidase homolog 3,mucin-5AC,ovoinhibitor,nucleobindin-2,calciumbinding protein(MW:4.5×10~4)and glucose-regulated protein(MW:7.8×10~4).The properties of these proteins are closely related to the bioactivities of EBN.Therefore,this article can provide inspiration for further research on the efficacy of EBN.展开更多
在已有的投影后变分(Variation After Projection,VAP)方法的基础上,进一步考虑宇称投影,VAP计算可将模型空间扩展至多个主大壳.然而,在多主壳的壳模型计算中,质心问题需要额外处理.由于现实壳模型哈密顿量不具有平移不变性,多主壳模型...在已有的投影后变分(Variation After Projection,VAP)方法的基础上,进一步考虑宇称投影,VAP计算可将模型空间扩展至多个主大壳.然而,在多主壳的壳模型计算中,质心问题需要额外处理.由于现实壳模型哈密顿量不具有平移不变性,多主壳模型空间的波函数会有质心部分的混杂,需要把质心部分从波函数中分离出来,以便得到纯净的内部波函数.这里,VAP计算也需要处理相同的质心问题.采用与标准壳模型完全一致的办法,实现了VAP波函数质心部分的有效分离.作为新方法的初步应用,我们在psd模型空间中计算了12C的正负宇称低激发态.结果表明,无论晕态还是非晕态,VAP方法仅采用几个HF真空态,就已能给出非常好的壳模型近似结果.至此,本文发展的VAP新方法,可以计算壳模型中所有类型的低激发态.展开更多
The impacts of elevation on fires in a ceiling vented compartment were investigated experimentally. The flame behavior of elevated fires was recorded. Various parameters including the fuel mass loss rate, the light ex...The impacts of elevation on fires in a ceiling vented compartment were investigated experimentally. The flame behavior of elevated fires was recorded. Various parameters including the fuel mass loss rate, the light extinction coefficient, the oxygen concentration and the gas temperature were measured. Results indicated that the variations of the flame behavior were consistent with that of the fuel mass loss rate. The fire location significantly impacted the light extinction coefficient, the oxygen concentration and the gas temperature, which all showed distinct stratification phenomena. For a higher elevated fire, the average fuel loss rate and the overall light extinction coefficient were smaller, the oxygen concentration was higher and the gas temperature was lower. In addition, the smoke descending was slower. From the perspective of those parameters the fire was less hazardous if the fire was elevated higher, which was totally different from the elevated fires in closed compartments.展开更多
The lunar surface is a typical vacuum environment,and its harsh heat rejection conditions bring great challenges to the thermal control technology of the exploration mission.In addition to the radiator,the sublimator ...The lunar surface is a typical vacuum environment,and its harsh heat rejection conditions bring great challenges to the thermal control technology of the exploration mission.In addition to the radiator,the sublimator is recommended as one of the promising options for heat rejection.The sublimator makes use of water to freeze and sublimate in a porous medium,rejecting heat to the vacuum environment.The complex heat and mass transfer process involves many physical phenomena such as the freezing and sublimation phase change of water in the porous medium and the movement of the phase-change interface.In this paper,the visualized ground-based experimental approaches of space sublimation cooling were presented to reveal the moving law of threephase point and the growth phenomenon of ice-peak and icicle in microchannels under vacuum conditions.The visualized experiments and results prove that the freezing ice is divided into the porous ice-peak and the transparent icicle.As the sublimation progresses,the phase-change interface moves downward steadily,the length of the ice-peak increases,but the icicle decreases.The visualized experiments of space sublimation cooling in the capillary have guiding significance to reveal the sublimation cooling mechanism of water in the sublimator for lunar exploration missions.展开更多
文摘在已有的投影后变分(variation after projection,VAP)方法的基础上,进一步考虑宇称投影。由此,VAP计算可将模型空间扩展至多个主大壳。考虑多个主大壳,VAP计算需要处理质心问题。对于质心修正,采用与标准壳模型完全一致的办法,将波函数的质心部分进行分离。在已有的VAP方法中,只能计算正宇称低激发态。采用新方法,在psd模型空间中计算了12 C的正负宇称低激发态。通过与壳模型(shell model,SM)精确值进行比较,无论正宇称态,还是负宇称态,都得到了非常好的近似结果。至此,VAP新方法可以计算壳模型中所有类型的低激发态。这是首次能够同时计算原子核正负宇称态的VAP计算。
文摘With the development of mobile technology, especially the development of 3G and mobile IP, the computational capacity of handsets is becoming more and more powerful, which provides a new method to solve the difficulties encountered in real time GIS accessing caused by the characteristics of mobility and remoteness of fieldwork in oilfield. On the basis of studying in-depth on the technologies of J2ME platform, Mobile SVG and mobile data transfer, etc., and in accordance with the actual situation of oilfield, the design framework of oilfield mobile GIS service is put forward and the schemes of key technologies are given in this paper, which establishes the technical foundation for the construction of “Digital Oilfield”.
基金The authors would like to thank for the financial support from the National Natural Science Foundation of China(No.31901374)Foundation of High-level Talents of Anhui Province(18030701150).
文摘Bamboo vascular bundle fiber and parenchyma(BP)are separated by high-temperature treatment with saturated steam.Bamboo vascular bundle fiber is widely used in the market,but how to develop and utilize parenchyma tissue is a difficult problem.The sulfated cellulose nanofibers(ANFs)were obtained by sulfating BP with a deep eutectic solvent(DES),which provided a theoretical basis for the value-added utilization of BP.Using DES as the reaction medium and reagent,the BP was grafted with a sulfonic acid group to form a gel substance in water,ANFs and nanocellulose gel were obtained by ultrasonic cell crusher.The highest yield of ANFS was 75%.The width of the ANFs was about 3 nm,and a small number of nanofiber aggregates existed at the same time.A high aspect ratio of ANFs,due to their high viscosity,has potential applications as enhancers at low concen-trations.Lewis acid(ZnCl 2)added based on binary(DES)greatly improved the thermal stability of the ANFs and maintained the crystal form of cellulose I.
基金The Authors acknowledge funding support by the National Key R&D Program of China(2017YFC0703501)The authors wish to acknowledge the National Natural Science Foundation of China(Grant No.32071700).
文摘In this study,the effects of three different particle sizes of wood wastes(A=–8+12 mesh;B=–12+20 mesh;C=–20+30 mesh)and factory shavings(D)on the properties of particleboard were investigated.According to the test results,three-layer particleboard was designed.Particleboard face layers made with mixture of A,B,and C.The core layer made with D.The ratio of core layer to face layers is 50:50.Three-layer particleboard were fabricated with 12%urea-formaldehyde(UF)resins and three different high voltage electrostatic field intensities(0 kv,30 kv,60 kv).The internal bond(IB)strength,modulus of rupture(MOR),modulus of elasticity(MOE),thickness swelling(TS),and water absorption(WA)of particleboard were evaluated.The density distribution of the three-layer particleboard were examined by vertical density profiles(VDP),and the bonding mechanism and functional groups changes in the particles were analyzed by FTIR analysis.The results showed that HVEF treatment intensity play a remarkable role in properties of particleboard.The particleboard with higher electrostatic field intensities treatment has higher MOE,MOR,IB,and TS.Under HVEF treatment(60 kv),the MOR,modulus of MOE,and IB of three-layer particleboard were 23.61 N/mm^(2),2787.09 N/mm^(2),and 0.86 N/mm^(2),respectively.FTIR indicated that the surface activity of wood particles was increased electric field treatment.
文摘To make a large area of dredger fill silt surface layer form working face and subsequent construction problems, the project conducts the bamboo network reinforcement in the silt surface layer. It makes the surface layer bearing capacity to meet the construction requirement of deep processing. Based on Shantou Municipal Road Embankment Treatment Engineering and the project, the bamboo network reinforcement technology to reinforce the dredger fill super soft soil surface layer is used. The results show that the bearing capacity of hydraulic fill super soft soil surface layer is 32.6 kPa after 3 months treatment. The surface layer bearing capacity after 3 months treatment improved 323% than the early treatment and increased 695% than no processing. The results indicate that the reinforcement effect is outstanding and provide the basis for drafting the dredger fill super soft soil surface layer treatment plan.
文摘With the rapid development of mobile communication and computer network technologies, the new mobile learning mode has been accepted by more and more people. In this paper, taking the learning system under mobile environment and from the perspective of necessary theoretic knowledge and relative technologies for mobile learning, the structural frame of the mobile learning system was discussed and constructed. According to this structural frame, the learning system under mobile environment was designed and applied into the OS course.
基金supported by grants from the National Key R&D Program of China(2017YFE0103400)the National Nature Science Foundation of China(81470628).
文摘Parvalbumin-positive retinal ganglion cells(PV+RGCs)are an essential subset of RGCs found in various species.However,their role in transmitting visual information remains unclear.Here,we characterized PV+RGCs in the retina and explored the functions of the PV+RGC-mediated visual pathway.By applying multiple viral tracing strategies,we investigated the downstream of PV+RGCs across the whole brain.Interestingly,we found that the PV+RGCs provided direct monosynaptic input to PV+excitatory neurons in the superficial layers of the superior colliculus(SC).Ablation or suppression of SC-projecting PV+RGCs abolished or severely impaired the flight response to looming visual stimuli in mice without affecting visual acuity.Furthermore,using transcriptome expression profiling of individual cells and immunofluorescence colocalization for RGCs,we found that PV+RGCs are predominant glutamatergic neurons.Thus,our findings indicate the critical role of PV+RGCs in an innate defensive response and suggest a non-canonical subcortical visual pathway from excitatory PV+RGCs to PV+SC neurons that regulates looming visual stimuli.These results provide a potential target for intervening and treating diseases related to this circuit,such as schizophrenia and autism.
基金financially supported by the Fundamental Research Funds for the Central Universities(lzujbky-2022-ct03)。
文摘Edible bird’s nest(EBN)is a kind of natural invigorant with a long history of consumption in Asia,especially in China.EBN is formed by mixing the saliva of swiftlets(Aerodramus)with feathers and other components during the breeding season.Proteins are the most important nutrient in EBN.By studying proteins in EBN,we can not only elucidate their components at the molecular level,but also study their bioactivities.Therefore,it is of great significance to study the proteins in EBN.Previous research on the proteins in EBN was preliminary and cursory,and no one has summarized and analyzed the proteins in EBN and correlated the bioactivities of these proteins with the biological functions of EBN.This article focused on the proteins in EBN,listed the proteins identified in different proteomic studies,and introduced the sources,structures and bioactivities of the most frequently identified proteins,including acidic mammalian chitinase,lysyl oxidase homolog 3,mucin-5AC,ovoinhibitor,nucleobindin-2,calciumbinding protein(MW:4.5×10~4)and glucose-regulated protein(MW:7.8×10~4).The properties of these proteins are closely related to the bioactivities of EBN.Therefore,this article can provide inspiration for further research on the efficacy of EBN.
文摘在已有的投影后变分(Variation After Projection,VAP)方法的基础上,进一步考虑宇称投影,VAP计算可将模型空间扩展至多个主大壳.然而,在多主壳的壳模型计算中,质心问题需要额外处理.由于现实壳模型哈密顿量不具有平移不变性,多主壳模型空间的波函数会有质心部分的混杂,需要把质心部分从波函数中分离出来,以便得到纯净的内部波函数.这里,VAP计算也需要处理相同的质心问题.采用与标准壳模型完全一致的办法,实现了VAP波函数质心部分的有效分离.作为新方法的初步应用,我们在psd模型空间中计算了12C的正负宇称低激发态.结果表明,无论晕态还是非晕态,VAP方法仅采用几个HF真空态,就已能给出非常好的壳模型近似结果.至此,本文发展的VAP新方法,可以计算壳模型中所有类型的低激发态.
基金partially supported by the National Key Research and Development Program of China(2016YFA0600104)supported by donations made by Delos Living LLC,and the Cyrus Tang Foundation+2 种基金supported by the National Natural Science Foundation of China(41471419)Beijing Institute of Urban Planningsupported by the Fundamental Research Funds for the Central Universities(CCNU19TD002).
基金supported by National Natural Science Foundation of China (Project no. 50976109 and no. 51206157)the Research Fund for the Doctoral Program of Higher Education of China (Grant no. 20123402110048)a Grant from CityU (Project No. 7002577)
文摘The impacts of elevation on fires in a ceiling vented compartment were investigated experimentally. The flame behavior of elevated fires was recorded. Various parameters including the fuel mass loss rate, the light extinction coefficient, the oxygen concentration and the gas temperature were measured. Results indicated that the variations of the flame behavior were consistent with that of the fuel mass loss rate. The fire location significantly impacted the light extinction coefficient, the oxygen concentration and the gas temperature, which all showed distinct stratification phenomena. For a higher elevated fire, the average fuel loss rate and the overall light extinction coefficient were smaller, the oxygen concentration was higher and the gas temperature was lower. In addition, the smoke descending was slower. From the perspective of those parameters the fire was less hazardous if the fire was elevated higher, which was totally different from the elevated fires in closed compartments.
基金primarily funded by the cooperative project offered by Beijing Key Laboratory of Space Thermal Control Technologyfunded by China Postdoctoral Science Foundation(No.2020 M671618)。
文摘The lunar surface is a typical vacuum environment,and its harsh heat rejection conditions bring great challenges to the thermal control technology of the exploration mission.In addition to the radiator,the sublimator is recommended as one of the promising options for heat rejection.The sublimator makes use of water to freeze and sublimate in a porous medium,rejecting heat to the vacuum environment.The complex heat and mass transfer process involves many physical phenomena such as the freezing and sublimation phase change of water in the porous medium and the movement of the phase-change interface.In this paper,the visualized ground-based experimental approaches of space sublimation cooling were presented to reveal the moving law of threephase point and the growth phenomenon of ice-peak and icicle in microchannels under vacuum conditions.The visualized experiments and results prove that the freezing ice is divided into the porous ice-peak and the transparent icicle.As the sublimation progresses,the phase-change interface moves downward steadily,the length of the ice-peak increases,but the icicle decreases.The visualized experiments of space sublimation cooling in the capillary have guiding significance to reveal the sublimation cooling mechanism of water in the sublimator for lunar exploration missions.