In this paper,a novel method is proposed and employed to design a single diffractive optical element(DOE) for implementing spectrum-splitting and beam-concentration(SSBC) functions simultaneously.We develop an opt...In this paper,a novel method is proposed and employed to design a single diffractive optical element(DOE) for implementing spectrum-splitting and beam-concentration(SSBC) functions simultaneously.We develop an optimization algorithm,through which the SSBC DOE can be optimized within an arbitrary thickness range according to the limitations of modern photolithography technology.Theoretical simulation results reveal that the designed SSBC DOE has a high optical focusing efficiency.It is expected that the designed SSBC DOE should have practical applications in high-efficiency solar cell systems.展开更多
针对串行抵消列表(Successive Cancellation List,SCL)译码框架下基于搜索集的路径分裂选择策略的缺陷,提出两种改进策略:基于可靠性函数的路径分裂策略和依靠辅助路径度量值(Auxiliary Path Metric,APM)的剪枝策略。在此基础上,提出一...针对串行抵消列表(Successive Cancellation List,SCL)译码框架下基于搜索集的路径分裂选择策略的缺陷,提出两种改进策略:基于可靠性函数的路径分裂策略和依靠辅助路径度量值(Auxiliary Path Metric,APM)的剪枝策略。在此基础上,提出一种新的译码算法——基于可靠性函数的路径分裂选择策略辅助串行抵消列表(Path Splitting Selecting Strategy Based on Reliability Function under the Successive Cancellation List,PSS-RF-SCL)译码算法。该算法在译码阶段,每个信息比特在进行路径分裂前,会计算所有路径的路径度量(Path Metric,PM)值。利用这些PM值,进一步计算该比特的可靠性函数值。算法将可靠性函数值低于其平均值(即阈值α)的信息比特视为需要进行路径分裂的比特,从而减少了多余的路径分裂次数。此外,算法计算每条路径的APM值,并将APM值高于正确译码路径的APM平均值(即阈值β)的路径视为不可靠路径,对不可靠路径进行剪枝,有效控制了译码列表总数。仿真结果表明,相较于传统的基于搜索集的路径分裂策略辅助的SCL译码算法,所提出的PSS-RF-SCL译码算法在保持相同译码性能的前提条件下,显著降低了译码复杂度。展开更多
寻找高效的直接Z-型异质结构光催化剂分解水制氢,被认为是解决能源危机和环境问题的有效途径之一.本工作采用基于密度泛函理论(DFT)的第一性原理计算方法,对构建的二维希托夫紫磷烯(HP)/SnS2异质结的电子结构、光学性质以及光催化性能...寻找高效的直接Z-型异质结构光催化剂分解水制氢,被认为是解决能源危机和环境问题的有效途径之一.本工作采用基于密度泛函理论(DFT)的第一性原理计算方法,对构建的二维希托夫紫磷烯(HP)/SnS2异质结的电子结构、光学性质以及光催化性能开展了系统研究.杂化泛函的计算结果表明,HP/SnS2异质结为直接带隙半导体,其带隙值为1.30 eV.交错的能带结构及其层间电荷转移诱导的内建电场诱发的直接Z-型载流子迁移机制,使之具有很强的氧化还原能力引发光解水的反应.光照下,HP侧的光生电子和SnS2侧的空穴提供的外电势能够大幅度降低HP/SnS2异质结析氢反应(HER)和析氧反应(OER)的吉布斯自由能,从而使其具有远小于各自单层材料的吉布斯自由能,表现出优异的析氢活性和析氧活性.此外,双轴应变可以有效调控HP/SnS2异质结的光催化能力以及光吸收特性.在应变为-10%的时候,HP/SnS2异质结在可见光范围内的光吸收能力达到最强,光吸收系数可高达1.71×10^(6)cm^(-1).通过比较水的氧化还原电位发现,当应变在-10%~8%范围之间的时候,HP/SnS2异质结均可满足光催化全解水的条件,其太阳能到氢能(Solar to Hydrogen,STH)转换效率最高可达到54.90%,远超10%的商业要求.综上所述,HP/SnS2异质结是一种具有研究价值和应用潜力的全解水光催化剂材料.展开更多
The heterogeneity of applications and their divergent resource requirements lead to uneven traffic distribution and imbalanced resource utilization across data center networks(DCNs).We propose a fine-grained baseband ...The heterogeneity of applications and their divergent resource requirements lead to uneven traffic distribution and imbalanced resource utilization across data center networks(DCNs).We propose a fine-grained baseband function reallocation scheme in heterogeneous optical switching-based DCNs.A deep reinforcement learning-based functional split and resource mapping approach(DRL-BFM)is proposed to maximize throughput in high-load server racks by implementing load balancing in DCNs.The results demonstrate that DRL-BFM improves the throughput by 20.8%,22.8%,and 29.8%on average compared to existing algorithms under different computational capacities,bandwidth constraints,and latency conditions,respectively.展开更多
Using the cross correlation function analysis method, this paper discusses shear wave splitting and crack-inducedanisotropy in the crust beneath Tangshan, North China, by the digital data from Tangshan strong ground m...Using the cross correlation function analysis method, this paper discusses shear wave splitting and crack-inducedanisotropy in the crust beneath Tangshan, North China, by the digital data from Tangshan strong ground monon temporary arrays. Sixteen of twenty-one stations in the arrays recorded earthquake events available forstudying from 1982 to 1984. Having calculated 131 available records, we get slower shear wave time delay r andfaster shear wave polarization azimuth Paz in Tangshan region, and the cracks density s is got further fromthem. The analysis shows that the stress field is very complicated in Tangshan region and has strongly regionalfeature. Because of the complicated distribution of faults, different shear wave splitting characteristics are shownin 16 stations, scattered r and different Paz. And they also were observed that the r and PaZ values were diversewithin the time scale of hours in more than one station. In Tangshan region the average results of r, Paz and Bare 0. 0071 s. km-1, northwest-west near to east-west and 0.022 respectively. Meantime, the standard devia.tions were calculated in this paper.展开更多
β-Ge3N4 loaded with nanoparticulate RuO2 as a cocatalyst is the first successful non-oxide photocatalyst for overall water splitting.To get an insight into the working mechanism of this particular photocatalytic syst...β-Ge3N4 loaded with nanoparticulate RuO2 as a cocatalyst is the first successful non-oxide photocatalyst for overall water splitting.To get an insight into the working mechanism of this particular photocatalytic system,we have calculated geometrical structures of low-index surfaces forβ-Ge3N4.Analysis of surface energies indicates that the most preferentially exposed surface is(100).The band gap of surface is narrower than that of bulk due to the dangling bonds.Dissociative water adsorption on(100)surface is thermodynamically favorable.The adsorption behavior of(RuO2)n(n=2,3,and 4)clusters on theβ-Ge3N4(100)surface has been explored.It is found that all the clusters bind to(100)surface strongly by forming interfacial bonds so that the adsorptions are exothermic processes.The calculation on density of states forβ-Ge3N4(100)surface loaded with(RuO2)nclusters reveals that photo-induced electrons tend to accumulate on(RuO2)nclusters and holes tend to stay inβ-Ge3N4.Based on the theoretical indication of Type-II staggered band alignment,we have proposed that in photocatalytic water splitting reaction,oxygen evolution reaction is inclined to occur on the surface ofβ-Ge3N4 while hydrogen evolution reaction is apt to occur on(RuO2)nclusters.In a word,loading RuO2 nanoparticles as a reduction cocatalyst benefits the charge separation inβ-Ge3N4.Furthermore,attaching(RuO2)nclusters ontoβ-Ge3N4(100)surface results in the redshift of absorption edge and the increase of absorption intensity.Our calculations have reasonably explained the experimental observation on the decomposition of water into H2 and O2 after loading RuO2 cocatalyst inβ-Ge3N4 photocatalyst.展开更多
In this paper, we report on a series of computational simulations on hydrogen bonding in two ice phases (Ih and Ic) using CASTEP with PW91 and RPBE exchange-correlation based on ab initio density functional theory. ...In this paper, we report on a series of computational simulations on hydrogen bonding in two ice phases (Ih and Ic) using CASTEP with PW91 and RPBE exchange-correlation based on ab initio density functional theory. The strength of the H-bond is correlated with intramolecular O-H stretching, and the energy splitting exists for both the H-bond and covalent O-H stretching. By analyzing the dispersion relationship of to(q), we observe the separation of the longitudinal optic (LO) mode from transverse optic (TO) mode at the gamma point, seemingly interpreting the controversial two H-bond peaks in the vibrational spectrum of ice recorded by inelastic incoherent neutron scattering experiments. The test of ambient environment on phonon density of sates (PDOS) shows that the relaxed tetrahedral structure is the most stable structural configuration for water clusters.展开更多
To better understand the effect of a new split variant of human asialoglycoprotein receptor (ASGPR H1b) on ASGPR ligands’ binding ability, we established a functional cell line which expresses ASGPR.The full lengths ...To better understand the effect of a new split variant of human asialoglycoprotein receptor (ASGPR H1b) on ASGPR ligands’ binding ability, we established a functional cell line which expresses ASGPR.The full lengths of ASGPRH1a and H2c fragments from human liver were amplified by reverse transcript PCR (RT-PCR) and inserted into eukaryotic expression vector pIRES2EFP, pCDNA3.1 (Zeo+) respectively.The recombinants were cotransfected into HeLa cells.After selection by using Neocin and Zeocin, a stably transfected cell line was established, which was designated 4-1-6.The transcription and expression of ASGPRH1a and H2c in 4-1-6 were confirmed by RT-PCR, Western blotting and immunofluorescence.The endocytosis function of the artificial "ASGPR" on the surface of 4-1-6 was tested by FACS.It was found that the cell line 4-1-6 could bind ASGPR natural ligand molecular asialo-orosomucoid (ASOR).After the eukaryotic plasmid H1b/pCDNA3.1 (neo) was transfected into cell line 4-1-6, H1b did not down-regulate the ligand binding ability of ASGPR.The eukaryotic expression plasmid H1b/pcDNA3.1 (neo) and H2c/pcDNA3.1 (neo) were co-transfected transiently into Hela cell.Neither single H1b nor H1b and H2c could bind ASOR.In conclusion, a functional cell line of human asialoglycoprotein receptor (ASGPR) which expresses both H1a and H2c stably was established.The new split variant H1b has no effect on ASGPR binding to ASOR.ASGPRH1b alone can’t bind to ASOR, it yet can’t form functional complex with ASGPRH2c.展开更多
基金Project supported by the National Basic Research Program of China (Grant No. 2011CB301801)the National Natural Science Foundation of China (GrantNos. 91233202,10904099,11204188,61205097,and 11174211)
文摘In this paper,a novel method is proposed and employed to design a single diffractive optical element(DOE) for implementing spectrum-splitting and beam-concentration(SSBC) functions simultaneously.We develop an optimization algorithm,through which the SSBC DOE can be optimized within an arbitrary thickness range according to the limitations of modern photolithography technology.Theoretical simulation results reveal that the designed SSBC DOE has a high optical focusing efficiency.It is expected that the designed SSBC DOE should have practical applications in high-efficiency solar cell systems.
文摘针对串行抵消列表(Successive Cancellation List,SCL)译码框架下基于搜索集的路径分裂选择策略的缺陷,提出两种改进策略:基于可靠性函数的路径分裂策略和依靠辅助路径度量值(Auxiliary Path Metric,APM)的剪枝策略。在此基础上,提出一种新的译码算法——基于可靠性函数的路径分裂选择策略辅助串行抵消列表(Path Splitting Selecting Strategy Based on Reliability Function under the Successive Cancellation List,PSS-RF-SCL)译码算法。该算法在译码阶段,每个信息比特在进行路径分裂前,会计算所有路径的路径度量(Path Metric,PM)值。利用这些PM值,进一步计算该比特的可靠性函数值。算法将可靠性函数值低于其平均值(即阈值α)的信息比特视为需要进行路径分裂的比特,从而减少了多余的路径分裂次数。此外,算法计算每条路径的APM值,并将APM值高于正确译码路径的APM平均值(即阈值β)的路径视为不可靠路径,对不可靠路径进行剪枝,有效控制了译码列表总数。仿真结果表明,相较于传统的基于搜索集的路径分裂策略辅助的SCL译码算法,所提出的PSS-RF-SCL译码算法在保持相同译码性能的前提条件下,显著降低了译码复杂度。
文摘寻找高效的直接Z-型异质结构光催化剂分解水制氢,被认为是解决能源危机和环境问题的有效途径之一.本工作采用基于密度泛函理论(DFT)的第一性原理计算方法,对构建的二维希托夫紫磷烯(HP)/SnS2异质结的电子结构、光学性质以及光催化性能开展了系统研究.杂化泛函的计算结果表明,HP/SnS2异质结为直接带隙半导体,其带隙值为1.30 eV.交错的能带结构及其层间电荷转移诱导的内建电场诱发的直接Z-型载流子迁移机制,使之具有很强的氧化还原能力引发光解水的反应.光照下,HP侧的光生电子和SnS2侧的空穴提供的外电势能够大幅度降低HP/SnS2异质结析氢反应(HER)和析氧反应(OER)的吉布斯自由能,从而使其具有远小于各自单层材料的吉布斯自由能,表现出优异的析氢活性和析氧活性.此外,双轴应变可以有效调控HP/SnS2异质结的光催化能力以及光吸收特性.在应变为-10%的时候,HP/SnS2异质结在可见光范围内的光吸收能力达到最强,光吸收系数可高达1.71×10^(6)cm^(-1).通过比较水的氧化还原电位发现,当应变在-10%~8%范围之间的时候,HP/SnS2异质结均可满足光催化全解水的条件,其太阳能到氢能(Solar to Hydrogen,STH)转换效率最高可达到54.90%,远超10%的商业要求.综上所述,HP/SnS2异质结是一种具有研究价值和应用潜力的全解水光催化剂材料.
基金supported by the National Key R&D Program of China(Nos.2023YFB2905500 and 2023YFB2805302)the National Natural Science Foundation of China(No.62205026)the Beijing Institute of Technology Research Fund Program for Young Scholars,and the Open Fund of IPOC(BUPT)。
文摘The heterogeneity of applications and their divergent resource requirements lead to uneven traffic distribution and imbalanced resource utilization across data center networks(DCNs).We propose a fine-grained baseband function reallocation scheme in heterogeneous optical switching-based DCNs.A deep reinforcement learning-based functional split and resource mapping approach(DRL-BFM)is proposed to maximize throughput in high-load server racks by implementing load balancing in DCNs.The results demonstrate that DRL-BFM improves the throughput by 20.8%,22.8%,and 29.8%on average compared to existing algorithms under different computational capacities,bandwidth constraints,and latency conditions,respectively.
文摘Using the cross correlation function analysis method, this paper discusses shear wave splitting and crack-inducedanisotropy in the crust beneath Tangshan, North China, by the digital data from Tangshan strong ground monon temporary arrays. Sixteen of twenty-one stations in the arrays recorded earthquake events available forstudying from 1982 to 1984. Having calculated 131 available records, we get slower shear wave time delay r andfaster shear wave polarization azimuth Paz in Tangshan region, and the cracks density s is got further fromthem. The analysis shows that the stress field is very complicated in Tangshan region and has strongly regionalfeature. Because of the complicated distribution of faults, different shear wave splitting characteristics are shownin 16 stations, scattered r and different Paz. And they also were observed that the r and PaZ values were diversewithin the time scale of hours in more than one station. In Tangshan region the average results of r, Paz and Bare 0. 0071 s. km-1, northwest-west near to east-west and 0.022 respectively. Meantime, the standard devia.tions were calculated in this paper.
基金the National Natural Science Foundation of China under Grant 21473183the open fund of Key Laboratory of Computational Physical Sciences(Fudan University),Ministry of Education.
文摘β-Ge3N4 loaded with nanoparticulate RuO2 as a cocatalyst is the first successful non-oxide photocatalyst for overall water splitting.To get an insight into the working mechanism of this particular photocatalytic system,we have calculated geometrical structures of low-index surfaces forβ-Ge3N4.Analysis of surface energies indicates that the most preferentially exposed surface is(100).The band gap of surface is narrower than that of bulk due to the dangling bonds.Dissociative water adsorption on(100)surface is thermodynamically favorable.The adsorption behavior of(RuO2)n(n=2,3,and 4)clusters on theβ-Ge3N4(100)surface has been explored.It is found that all the clusters bind to(100)surface strongly by forming interfacial bonds so that the adsorptions are exothermic processes.The calculation on density of states forβ-Ge3N4(100)surface loaded with(RuO2)nclusters reveals that photo-induced electrons tend to accumulate on(RuO2)nclusters and holes tend to stay inβ-Ge3N4.Based on the theoretical indication of Type-II staggered band alignment,we have proposed that in photocatalytic water splitting reaction,oxygen evolution reaction is inclined to occur on the surface ofβ-Ge3N4 while hydrogen evolution reaction is apt to occur on(RuO2)nclusters.In a word,loading RuO2 nanoparticles as a reduction cocatalyst benefits the charge separation inβ-Ge3N4.Furthermore,attaching(RuO2)nclusters ontoβ-Ge3N4(100)surface results in the redshift of absorption edge and the increase of absorption intensity.Our calculations have reasonably explained the experimental observation on the decomposition of water into H2 and O2 after loading RuO2 cocatalyst inβ-Ge3N4 photocatalyst.
基金Project supported by the National Natural Science Foundation of China (Grant No.11075094)
文摘In this paper, we report on a series of computational simulations on hydrogen bonding in two ice phases (Ih and Ic) using CASTEP with PW91 and RPBE exchange-correlation based on ab initio density functional theory. The strength of the H-bond is correlated with intramolecular O-H stretching, and the energy splitting exists for both the H-bond and covalent O-H stretching. By analyzing the dispersion relationship of to(q), we observe the separation of the longitudinal optic (LO) mode from transverse optic (TO) mode at the gamma point, seemingly interpreting the controversial two H-bond peaks in the vibrational spectrum of ice recorded by inelastic incoherent neutron scattering experiments. The test of ambient environment on phonon density of sates (PDOS) shows that the relaxed tetrahedral structure is the most stable structural configuration for water clusters.
基金supported by grants from the National Major Science and Technology Special Project for Infectious Diseases of China (No.2008ZX10002-011)National High Technology Research and Development of China (Program 863) (No.2006AA02Z128)the National Natural Science Foundation of China (Nos.30700701,30571646)
文摘To better understand the effect of a new split variant of human asialoglycoprotein receptor (ASGPR H1b) on ASGPR ligands’ binding ability, we established a functional cell line which expresses ASGPR.The full lengths of ASGPRH1a and H2c fragments from human liver were amplified by reverse transcript PCR (RT-PCR) and inserted into eukaryotic expression vector pIRES2EFP, pCDNA3.1 (Zeo+) respectively.The recombinants were cotransfected into HeLa cells.After selection by using Neocin and Zeocin, a stably transfected cell line was established, which was designated 4-1-6.The transcription and expression of ASGPRH1a and H2c in 4-1-6 were confirmed by RT-PCR, Western blotting and immunofluorescence.The endocytosis function of the artificial "ASGPR" on the surface of 4-1-6 was tested by FACS.It was found that the cell line 4-1-6 could bind ASGPR natural ligand molecular asialo-orosomucoid (ASOR).After the eukaryotic plasmid H1b/pCDNA3.1 (neo) was transfected into cell line 4-1-6, H1b did not down-regulate the ligand binding ability of ASGPR.The eukaryotic expression plasmid H1b/pcDNA3.1 (neo) and H2c/pcDNA3.1 (neo) were co-transfected transiently into Hela cell.Neither single H1b nor H1b and H2c could bind ASOR.In conclusion, a functional cell line of human asialoglycoprotein receptor (ASGPR) which expresses both H1a and H2c stably was established.The new split variant H1b has no effect on ASGPR binding to ASOR.ASGPRH1b alone can’t bind to ASOR, it yet can’t form functional complex with ASGPRH2c.