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基于SSA-BP网络模型的Hong-Ou-Mandel干涉时延测量研究及其在量子陀螺仪中的应用
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作者 翟艺伟 李旺 《物理学报》 SCIE EI CAS CSCD 北大核心 2023年第13期245-251,共7页
作为航空航天导航系统的重要器件,高灵敏度的光学陀螺仪一直是国内外科研工作者的研究重点.经典光学陀螺仪因真空零点波动使其灵敏度受到散粒噪声极限的制约,无法满足日益发展的量子导航需求.本文提出了基于频率纠缠源及Hong-Ou-Mandel(... 作为航空航天导航系统的重要器件,高灵敏度的光学陀螺仪一直是国内外科研工作者的研究重点.经典光学陀螺仪因真空零点波动使其灵敏度受到散粒噪声极限的制约,无法满足日益发展的量子导航需求.本文提出了基于频率纠缠源及Hong-Ou-Mandel(HOM)干涉的量子陀螺仪方案,利用SSA-BP神经网络模型模拟不同的泵浦光和非线性晶体参数,以预测HOM干涉图谱的特性参量干涉可见度及干涉宽度.结合量子Fisher信息理论,获得时延差的最大量子Fisher信息可达1.999,计算得出时延差的不确定度与散粒噪声极限的最小比值为0.707,并依据量子陀螺仪时延差与旋转角速度的关系,验证出旋转角速度的测量灵敏度较经典光学陀螺仪提高了2个数量级.证明上述方案可以实现超越散粒噪声极限的测量灵敏度,能为后续量子陀螺仪的实验验证提供理论支持. 展开更多
关键词 Hong-Ou-mandel干涉 时延测量 量子陀螺仪 麻雀搜索算法
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圆球土样Biot固结的级数解与Mandel—Cryer效应 被引量:12
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作者 纪多辙 《工程力学》 EI CSCD 北大核心 2002年第4期24-28,共5页
圆球土样固结是发现Mandel-Cryer效应的一个著名例子。本文采用将圆球土样的Biot固结解分解为弹性静力学解和渗流拟动态解叠加的方法,利用球Bessel函数的正交性质,给出了定量分析这一著名例子的封闭级数解,并具体分析了Mandel-Cryer效... 圆球土样固结是发现Mandel-Cryer效应的一个著名例子。本文采用将圆球土样的Biot固结解分解为弹性静力学解和渗流拟动态解叠加的方法,利用球Bessel函数的正交性质,给出了定量分析这一著名例子的封闭级数解,并具体分析了Mandel-Cryer效应产生的原因和影响Mandel-Cryer效应的因素。 展开更多
关键词 圆球土样 BIOT固结 级数解 mandel-Cryer效应 弹性静力学解 全场渗流固结
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Kerr介质中V型三能级原子与压缩相干态光场相互作用系统Mandel因子的演化特性 被引量:4
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作者 刘素梅 《量子电子学报》 CAS CSCD 北大核心 2004年第6期829-836,共8页
研究了在充满Kerr介质的高Q腔中V型三能级原子与压缩相干态光场相互作用系统Mandel因子Q(t)的时间演化规律;讨论了Kerr介质强度系数μ、光场压缩因子γ、光场相干振幅分量模平方|α|2和原子-场的耦合系数λ对光子统计分布特性的影响。... 研究了在充满Kerr介质的高Q腔中V型三能级原子与压缩相干态光场相互作用系统Mandel因子Q(t)的时间演化规律;讨论了Kerr介质强度系数μ、光场压缩因子γ、光场相干振幅分量模平方|α|2和原子-场的耦合系数λ对光子统计分布特性的影响。结果发现:μ、γ、|α|2和λ都影响了Mandel因子Q(t)演化曲线量子崩塌-复苏效应的周期性,同时,也影响了受激辐射场的光子统计分布的状态和特性。 展开更多
关键词 量子光学 KERR介质 Sub-Poisson光子统计 压缩相干态光场 mandel因子Q(t) V型三能级原子
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饱和土的球对称固结与Mandel-Cryer效应 被引量:2
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作者 张引科 昝会萍 《西安建筑科技大学学报(自然科学版)》 CSCD 北大核心 2007年第2期177-180,共4页
饱和土的固结问题是土力学的一个基本问题,在饱和土固结过程中往往伴有Mandel-Cryer效应,对Mandel-Cryer效应的理论研究尚不完善.以Biot饱和土理论为基础,通过直接求解饱和土球对称Biot固结方程,得到了球对称固结方程在真实空间的解析解... 饱和土的固结问题是土力学的一个基本问题,在饱和土固结过程中往往伴有Mandel-Cryer效应,对Mandel-Cryer效应的理论研究尚不完善.以Biot饱和土理论为基础,通过直接求解饱和土球对称Biot固结方程,得到了球对称固结方程在真实空间的解析解.数值计算结果充分表现了饱和土三维固结过程中孔隙水压力在空间的分布和随时间的变化,直观反映了Mandel-Cryer效应的发展过程,同时给出了土体泊松比对Mandel-Cryer效应的影响规律. 展开更多
关键词 BIOT理论 饱和土固结 mandel-Cryer效应
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Biocatalytic synthesis of (R)-(-)-mandelic acid from racemic mandelonitrile by a newly isolated nitrilase-producer Alcaligenes sp. ECU0401 被引量:12
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作者 Yu Cai He Jian He Xu +2 位作者 Yi Xu Li Ming Ouyang Jiang Pan 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第6期677-680,共4页
By using acetonitrile as the sole nitrogen source, a microbial strain with high nitrilase activity, named as Alcaligenes sp. ECU0401, was newly isolated from soil, which could enantioselectively transform racemic mand... By using acetonitrile as the sole nitrogen source, a microbial strain with high nitrilase activity, named as Alcaligenes sp. ECU0401, was newly isolated from soil, which could enantioselectively transform racemic mandelonitrile into (R)-(?)-mandelic acid, with an enantiomeric excess of >99.9%. 展开更多
关键词 mandelonitrile NITRILASE (R)-()-mandelic acid SCREENING Alcaligenes sp. ECU0401
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饱和软土固结的Mandel-Cryer效应及影响因素研究 被引量:4
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作者 汪江 《华东交通大学学报》 2013年第5期52-56,共5页
采用Biot固结理论分析饱和软土的渗流固结问题时,在固结“初期”,会出现隙水压力升高,且大于初始孔压的现象,即Mandel-Cryer效应。基于Biot固结理论,采用有限元计算方法,分析了深度、模量、泊松比和渗透系数对Mandel-Cryer的影响... 采用Biot固结理论分析饱和软土的渗流固结问题时,在固结“初期”,会出现隙水压力升高,且大于初始孔压的现象,即Mandel-Cryer效应。基于Biot固结理论,采用有限元计算方法,分析了深度、模量、泊松比和渗透系数对Mandel-Cryer的影响。研究结果显示:随着深度的增加,归一化孔压值增大3~17 m,归一化值为1.01~1.07,曼德尔效应开始时间与深度呈指数关系;模量越大,曼德尔效应的时间越提前,模量对归一化孔压值影响较小,最大归一化孔压值为1.06~1.07;泊松比对曼德尔效应的影响最大,泊松比越小,曼德尔效应越明显,孔压归一化值越大,时间越推迟;渗透系数对Mandel-Cryer效应的影响主要体现在对发生的时间方面,渗透系数越小,Mandel-Cryer越推迟。 展开更多
关键词 饱和软土 BIOT理论 mandel-Cryer效应 有限元
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纠缠光子对的级联Hong-Ou-Mandel干涉研究及其在多时延参数测量中的应用 被引量:4
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作者 翟艺伟 董瑞芳 +3 位作者 权润爱 项晓 刘涛 张首刚 《物理学报》 SCIE EI CAS CSCD 北大核心 2021年第12期22-29,共8页
基于纠缠光子对的Hong-Ou-Mandel(HOM)干涉仪在量子精密测量等领域有着重要应用.本文提出了利用一个级联HOM干涉仪实现多个独立时延参数的同时测量方案.通过理论分析得出纠缠光子对经过多个50:50分束器级联传输后,其HOM二阶量子干涉图... 基于纠缠光子对的Hong-Ou-Mandel(HOM)干涉仪在量子精密测量等领域有着重要应用.本文提出了利用一个级联HOM干涉仪实现多个独立时延参数的同时测量方案.通过理论分析得出纠缠光子对经过多个50:50分束器级联传输后,其HOM二阶量子干涉图谱中凹陷位置与各级传输路径间独立时延参数的对应关系,因此可通过记录各个凹陷位置的时延值实现多个独立时延参数的同时测量.在此基础上搭建了基于频率一致纠缠光子对的二级级联HOM干涉测量装置,通过实验上得到的具有两个对称凹陷的二阶量子干涉图谱,实现了两级传输路径间两个独立时延参数τ1和τ2的同时测量,并分别获得了109 fs和98 fs的测量精度.上述研究结果为HOM干涉仪在多参量量子精密测量系统中的扩展应用奠定基础. 展开更多
关键词 Hong-Ou-mandel干涉仪 纠缠光子对 多时延参数 同时测量
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两个独立全光纤多通道光子纠缠源的Hong-Ou-Mandel干涉 被引量:1
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作者 李银海 许昭怀 +3 位作者 王双 许立新 周志远 史保森 《物理学报》 SCIE EI CAS CSCD 北大核心 2017年第12期49-55,共7页
独立光子源的干涉是实现复杂量子体系应用(比如多光子纠缠态产生和量子隐形传态等)的核心技术.利用100 GHz密集波分复用技术,实现了1.55μm全光纤多通道独立纠缠光子源的Hong-Ou-Mandel干涉,在不去除暗符合(随机符合计数)的情况下,可见... 独立光子源的干涉是实现复杂量子体系应用(比如多光子纠缠态产生和量子隐形传态等)的核心技术.利用100 GHz密集波分复用技术,实现了1.55μm全光纤多通道独立纠缠光子源的Hong-Ou-Mandel干涉,在不去除暗符合(随机符合计数)的情况下,可见度为53.2%±8.4%,去除暗符合可见度可达到82.9%±5.3%.给出了关于色散位移光纤中基于自发四波混频过程产生的单光子光谱纯度严格的理论描述,模拟了抽运脉冲宽度和滤波器带宽对单光子光谱纯度的影响,并给出了理论上的最佳条件(最佳的抽运脉冲宽度为8 ps,高斯滤波器带宽为40 GHz及以下).在测量Hong-Ou-Mandel干涉之前,先测量了液氮冷却状态下的色散位移光纤关联光子源的符合和随机符合比率,在抽运功率为23μW的情况下,最大比率可以达到131.Hong-Ou-Mandel干涉在高精度光学测量、测量装置无关的量子密钥分配等应用中扮演着极为重要的角色. 展开更多
关键词 密集波分复用 Hong-Ou-mandel干涉 色散位移光纤
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强聚焦泵浦产生纠缠光子的Hong-Ou-Mandel干涉 被引量:1
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作者 田颖 蔡吾豪 +3 位作者 杨子祥 陈峰 金锐博 周强 《物理学报》 SCIE EI CAS CSCD 北大核心 2022年第5期131-139,共9页
Hong-Ou-Mandel(HOM)干涉是光子的一种非经典效应,在量子光学中起到重要作用.偏硼酸钡(β-barium borate,BBO)具有较高的非线性效率,常被用来产生双光子态,进而展示HOM干涉.然而,在以前的实验中,人们往往使用带通滤光片对双光子的频谱... Hong-Ou-Mandel(HOM)干涉是光子的一种非经典效应,在量子光学中起到重要作用.偏硼酸钡(β-barium borate,BBO)具有较高的非线性效率,常被用来产生双光子态,进而展示HOM干涉.然而,在以前的实验中,人们往往使用带通滤光片对双光子的频谱进行过滤,所得光谱由带通滤光片直接决定,而对BBO晶体自身的原始光谱,特别是泵浦光强聚焦下的原始光谱,缺乏系统性研究.本文对泵浦光强聚焦条件下BBO晶体产生的双光子纠缠态光谱分布和HOM干涉进行了深入研究.理论计算发现,使用50 mm透镜聚焦的情况和无聚焦情况相比,下转换光的光谱宽度会增加7.4倍,HOM干涉条纹的宽度会减少为无聚焦情况的1/8,干涉条纹可见度会从53.0%提高到98.7%.实验上使用II型BBO晶体制备了能量-时间纠缠态,并进行了HOM干涉,获得了(86.6±1.0)%的干涉可见度.干涉可见度极大提高的原因在于强聚焦改善了光谱的对称性.此外,本文提出的不同入射角获得不同光谱分布的技术方案有望在未来应用于高维量子纠缠态的制备. 展开更多
关键词 Hong-Ou-mandel 干涉 偏硼酸钡晶体 聚束效应 量子信息
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Hong–Ou–Mandel interference with two independent weak coherent states 被引量:4
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作者 陈华 安雪碧 +4 位作者 伍娟 银振强 王双 陈巍 韩正甫 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第2期76-81,共6页
Recently, the Hong-Ou-Mandel (HOM) interference between two independent weak coherent pulses (WCPs) has been paid much attention due to the measurement-device-independent (MDI) quantum key distribution (QKD). ... Recently, the Hong-Ou-Mandel (HOM) interference between two independent weak coherent pulses (WCPs) has been paid much attention due to the measurement-device-independent (MDI) quantum key distribution (QKD). Using classical wave theory, articles reported before show that the visibility of this kind of HOM-type interference is 〈 50%. In this work, we analyze this kind of interference using quantum optics, which reveals more details compared to the wave theory. Analyses confirm the maximum visibility of 50%. And we conclude that the maximum visibility of 50% comes from the two single-photon states in WCPs, without considering the noise. In the experiment, we successfully approach the visibility of 50% by using WCPs splitting from the single pico-second laser source and phase scanning. Since this kind of HOM interference is immune to slow phase fluctuations, both the realized and proposed experiment designs can provide stable ways of high-resolution optical distance detection. 展开更多
关键词 Hong-Ou-mandel interference weak coherent states measurement-device-independent quantumkey distribution
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Soy Protein Isolate Film by Incorporating Mandelic Acid as Well as Through Fermentation Mediated by Bacillus Subtilis 被引量:2
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作者 Rakesh Kumar Priya Rani K.Dinesh Kumar 《Journal of Renewable Materials》 SCIE 2019年第2期103-115,共13页
Soy protein isolate(SPI)biopolymeric films were prepared by adding different contents of mandelic acid(1 to 5%wrt SPI)to glycerol plasticized SPI by solution casting method.Also,SPI was fermented by Bacillus subtilis ... Soy protein isolate(SPI)biopolymeric films were prepared by adding different contents of mandelic acid(1 to 5%wrt SPI)to glycerol plasticized SPI by solution casting method.Also,SPI was fermented by Bacillus subtilis to get fermented SPI films by solution casting.Molecular mass determination of mandelic acid incorporated and fermented SPI films was carried out by sodium dodecyl sulphate-polyacrylamide gel electrophoresis(SDS-PAGE).Mandelic acid incorporated and fermented SPI films were characterized by Fourier-transform infrared spectroscopy(FT-IR),dynamic mechanical analysis(DMA),tensile strength,water uptake and optical transmittance studies.Results indicated that incorporation of mandelic acid in SPI resulted in high tensile strength(8.03 MPa)and highα-relaxation(Tα)as well as low water uptake.On the other hand,films cannot be prepared from fermented SPI with SPI contents of 8%and 12%.However,film from fermented SPI with 16%SPI content could be prepared but it exhibited low tensile strength(3.18 MPa)and low Tαas well as high water uptake.The resulting mandelic acid incorporated SPI films were also subjected to antimicrobial studies.At all the concentration of mandelic acid,we can easily observe the antimicrobial effect in mandelic acid incorporated SPI films unlike fermented SPI films.This work will be helpful in fabricating antimicrobial SPI film from renewable resources. 展开更多
关键词 Soy protein isolate mandelic acid FERMENTATION FILM tensile properties antimicrobial properties
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Functional characterization of a novel microbial esterase identified from the Indian Ocean and its use in the stereoselective preparation of(R)-methyl mandelate 被引量:3
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作者 梁甲元 孙爱君 +4 位作者 张云 邓盾 王永飞 马三梅 胡云峰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第6期1269-1277,共9页
Genomic mining has identifi ed a novel microbial alkaline esterase from the Indian Ocean. This esterase was overexpressed in E. coli BL21(DE3) and further functionally characterized. Under optimal conditions(10 mmo... Genomic mining has identifi ed a novel microbial alkaline esterase from the Indian Ocean. This esterase was overexpressed in E. coli BL21(DE3) and further functionally characterized. Under optimal conditions(10 mmol/L substrate, p H 6.0, 2 h at 40 ℃), this esterase can hydrolyze racemic methyl mandelate to( R)-methyl mandelate with very high optical purity(e. e. 〉99%) and yield(nearly 90%). Interestingly, the stereoselectivity of this esterase is opposite to that of two previously reported lipases that can generate( S)-methyl mandelate through the hydrolysis of racemic methyl mandelate. No organic solvents or other additives were required to optimize the optical purity and production of the fi nal chiral product(R)-methyl mandelate, which can potentially simplify the production procedure of( R)-methyl mandelate catalyzed by esterase. 展开更多
关键词 alkaline esterase kinetic resolution (R)-methyl mandelate high optical purity opposite stereoselectivity
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Enantioselective extraction of mandelic acid enantiomers based on chiral ligand exchange 被引量:1
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作者 唐课文 黄可龙 《Journal of Central South University of Technology》 2005年第2期123-128,共6页
Based on the chiral ligand exchange, the distribution behavior of mandelic acid enantiomers, and the partition of Cu2+ at different pH values were studied in a water/alcohol two-phase system containing Cu2+ and N-n-(... Based on the chiral ligand exchange, the distribution behavior of mandelic acid enantiomers, and the partition of Cu2+ at different pH values were studied in a water/alcohol two-phase system containing Cu2+ and N-n-(dodecyl-L-proline(A).) The influences of the solvent sort, the pH value, the concentrations of Cu2+ and chiral ligand on the partition coefficient(K) and separation factor(α) were discussed. The experimental results show that the A formed has more stable ternary complex with D-mandelic acid enantiomer than with L-mandelic acid enantiomer. There is an important influence of the pH value on K and α. When the pH values are less than 3.5, the formation of binary complexes is thermodynamically unfavourable. K and α become maximum when pH values are above 3.5 and the molar ratio of the chiral ligand to Cu2+ is 2∶1. 展开更多
关键词 ligand exchange EXTRACTION chiral separation mandelic acid enantiomers
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Molecular Basis for Stereospecific Hydrolysis of Ethyl Mandelate by Thermophilic Esterase
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作者 ZHANG Guo-yan TAO Jin +1 位作者 ZHENG Liang-yu CAO Shu-gui 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第5期841-844,共4页
The stereospecific hydrolysis of mandelate can be effectively catalyzed by hyperthermophilic acylpeptide esterase APE 1547(Aeropyrum pernix esterase 1547). APE 1547 used in this reaction showed a remarkable stereodi... The stereospecific hydrolysis of mandelate can be effectively catalyzed by hyperthermophilic acylpeptide esterase APE 1547(Aeropyrum pernix esterase 1547). APE 1547 used in this reaction showed a remarkable stereodi-scrimination in favour of R-mandelic acid(99% e.e.) with an enantiomeric ratio E〉200. The results of computer simulation are consistent with the experimental results. It can be inferred that the R-substrate adopted a binding mode productive of the reaction due to the formation of the hydrogen bond at the active site of APE 1547. 展开更多
关键词 Hyperthermophilic acylpeptide esterase BIOCATALYST Stereospecific hydrolysis mandelic acid Computer simulation
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Optical Separation of Racemic Phenyl-alanine, and Structure of Complex Consisting of R-Phenylalanine and R-Mandelic Acid
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作者 HUZi-Qiang XUDuan-Jun +2 位作者 XUYuan-Zhi WUJing-Yun CHIANGMichaelY 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第1期38-40,共3页
The racemic phenylalanine has been separated by (R)-mandelic acid through the formation of diastereomeric molecular complex. The crystal of the title chiral complex (C8H8O3 C9H11NO2, Mr = 317.33) belongs to monoclinic... The racemic phenylalanine has been separated by (R)-mandelic acid through the formation of diastereomeric molecular complex. The crystal of the title chiral complex (C8H8O3 C9H11NO2, Mr = 317.33) belongs to monoclinic, space group C2 with a = 19.391(3), b = 5.715(4), c = 15.755(3) ? b = 115.23(1), V = 1579(1) 3, Z = 4, Dc = 1.335 g/cm3, F(000) = 672, m = 0.099 mm-1, R = 0.033 and wR = 0.060 for 1278 observed reflections (I > 2s(I)). The complex consists of (R)-mandelic acid and (R)-phenylalanine in 1:1 molar ratio, and the complex molecules form layered crystal structure by self-assembly through intermolecular H-bonding between carboxyl and carboxylate of the neighboring molecules. 展开更多
关键词 optical separation crystal structure mandelic acid PHENYLALANINE
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Two-Photon Interference Constructed by Two Hong–Ou–Mandel Effects in One Mach-Zehnder Interferometer
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作者 Rui Liu Ling-dun Kong +5 位作者 Zhon-Xiang Wang Yu Si Wen-Rong Qi Shuang-Yin Huang Chenghou Tu Yongnan Hui-Tian Wang 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第9期14-18,共5页
We present a two-photon interference experiment in a modified Mach-Zehnder (MZ) interferometer in which two Hong-Ou-Mandel effects occur in tandem and construct superposed two-photon states. The signal photons pass ... We present a two-photon interference experiment in a modified Mach-Zehnder (MZ) interferometer in which two Hong-Ou-Mandel effects occur in tandem and construct superposed two-photon states. The signal photons pass both the arms of the MZ interferometer while the idler photons pass one arm only. Interestingly, the probability of the idler photons emerging from any output port still shows a sine oscillation with the two-photon phase difference and it can be characterized only by the indistinguishability of the two-photon amplitudes. We also observe a two-photon interference pattern with a period being equal to the wavelength of the parametric photons instead of the two-photon photonie de Broglie wavelength due to the presence of two-photon phase difference, in particular, with complementary probabilities of finding the two-photon pairs in two output ports. The abundant observations can facilitate a more comprehensive understanding of the two-photon interference. 展开更多
关键词 mandel Effects in One Mach-Zehnder Interferometer OU Two-Photon Interference Constructed by Two Hong
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Biocatalytic stereoselective synthesis of methyl mandelates by engineering a cytochrome P450 hydroxylase
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作者 Lingzhi Xie Yun Zhang +6 位作者 Ruyue Zhang Haibo Cui Baodong Cui Wenyong Han Nanwei Wan Zhi Li Yongzheng Chen 《Green Synthesis and Catalysis》 2024年第2期88-93,共6页
Chiral methyl mandelates are useful synthons in organic transformation and pharmaceutical synthesis.Green synthesis of these valuable compounds by direct C–H activating oxidative hydroxylation has attracted keen inte... Chiral methyl mandelates are useful synthons in organic transformation and pharmaceutical synthesis.Green synthesis of these valuable compounds by direct C–H activating oxidative hydroxylation has attracted keen interest.Described herein is achieving the stereoselective and efficient bio-hydroxylation of methyl 2-phenylacetates to the chiral methyl mandelates by directed evolution of the cytochrome P450DA hydroxylase.In the present study,a new colorimetric high-throughput screening assay was successfully developed based on a dualenzyme cascade for the engineering of the P450DA's hydroxylation activity.Several beneficial variants with enhanced bio-hydroxylation activity were created by combining random mutagenesis and site-saturated/directed mutagenesis strategies.Whole-cell bio-hydroxylation of various methyl 2-phenylacetates using the best septupletmutant P450DA-11 yielded the corresponding chiral methyl mandelates in up to 92%isolated yields and>99%ee. 展开更多
关键词 Bio-hydroxylation Directed evolution Cytochrome P450 High-throughput screening Methyl mandelates
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Mandelic Acid Single-Crystal Growth:Experiments vs Numerical Simulations
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作者 Q.Tan S.A.Hosseini +2 位作者 A.Seidel-Morgenstern D.Thevenin H.Lorenz 《Communications in Computational Physics》 SCIE 2023年第1期77-100,共24页
Mandelic acid is an enantiomer of interest in many areas,in particular for the pharmaceutical industry.One of the approaches to produce enantiopure mandelic acid is through crystallization from an aqueous solution.We ... Mandelic acid is an enantiomer of interest in many areas,in particular for the pharmaceutical industry.One of the approaches to produce enantiopure mandelic acid is through crystallization from an aqueous solution.We propose in this study a numerical tool based on lattice Boltzmann simulations to model crystallization dynamics of(S)-mandelic acid.The solver is first validated against experimental data.It is then used to perform parametric studies concerning the effects of important parameters such as supersaturation and seed size on the growth rate.It is finally extended to investigate the impact of forced convection on the crystal habits.Based on there parametric studies,a modification of the reactor geometry is proposed that should reduce the observed deviations from symmetrical growth with a five-fold habit. 展开更多
关键词 mandelic acid phase-field model lattice Boltzmann method ventilation effect
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化学转化驱动杂质分离在实验教学中的应用——氟代扁桃酸的纯化新方法 被引量:1
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作者 陈洋 陈鹏 +2 位作者 宋宇阳 金玉雪 吴松 《大学化学》 CAS 2024年第6期253-263,共11页
基于“问题导向、兴趣驱动、自主探究”的综合实验教学理念,在有机化学实验教学中融入“化学转化驱动杂质分离”理论知识,设计创新综合实验。运用化学转化实现待纯化目标分子(α-氟苯基乙酸,简称“氟代扁桃酸”)与杂质(扁桃酸)的有效分... 基于“问题导向、兴趣驱动、自主探究”的综合实验教学理念,在有机化学实验教学中融入“化学转化驱动杂质分离”理论知识,设计创新综合实验。运用化学转化实现待纯化目标分子(α-氟苯基乙酸,简称“氟代扁桃酸”)与杂质(扁桃酸)的有效分离,产物纯度分别可达到98.7%和97.0%。整个实验中使用到的主要药品试剂价格低廉,易获取,且可回收再利用,充分体现了原子经济性和绿色化学思想。实验过程中,应用了多种有机化学实验的基本技能,包括减压蒸馏、浓缩脱溶、重结晶、过滤等必要实验技能,以及薄层色谱法、核磁共振等重要分析手段。熟练掌握这些重要的实验技能和分析手段,能够培养学生以基础理论指导实验、有效分离性质差异小的待测有机化合物、分析实验现象的能力,进一步提升本科生的学术修养、科学素养和综合运用知识解决实际问题的能力。 展开更多
关键词 氟代扁桃酸 扁桃酸 化学转化 分离方法 综合实验
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植物水杨酸/苦杏仁酸/壬二酸共载纳米乳的制备及祛痘功效研究
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作者 黄晓东 罗丹 +3 位作者 陈璇 王曦 洪延涵 刘卫 《中国美容医学》 CAS 2024年第11期6-10,共5页
目的:通过纳米载体技术将植物水杨酸、苦杏仁酸及壬二酸等活性成分进行包载,制备植物水杨酸/苦杏仁酸/壬二酸共载纳米乳(植酸素,产品批号:20220623),对其理化性质、体外透皮性能、抑菌活性及祛痘控油功效进行评价。方法:采用纳米电位粒... 目的:通过纳米载体技术将植物水杨酸、苦杏仁酸及壬二酸等活性成分进行包载,制备植物水杨酸/苦杏仁酸/壬二酸共载纳米乳(植酸素,产品批号:20220623),对其理化性质、体外透皮性能、抑菌活性及祛痘控油功效进行评价。方法:采用纳米电位粒径分析仪测试植酸素的粒径、PDI及电位;采用Franz扩散池法进行离体猪皮的透皮实验;建立痤疮丙酸杆菌和金黄色葡萄球菌活性抑制的实验方法;建立LPS诱导的细胞炎症模型及采用油红O法观察植酸素对SZ95细胞分泌油脂的影响。结果:测得植酸素粒径为(37.5±0.2)nm,PDI为(0.131±0.008),Zeta电位为(-25.1±1.2)mV。体外透皮实验结果表明,活性成分经纳米载体包裹后具有良好的皮肤渗透性及皮肤储留能力;抑菌实验结果表明,植酸素可抑制痤疮丙酸杆菌和金黄色葡萄球菌活性;细胞功效实验结果表明,与游离活性成分比较,植酸素可显著抑制RAW264.7细胞分泌炎症因子,抑制SZ95细胞分泌细胞脂滴。结论:植物水杨酸、苦杏仁酸及壬二酸经纳米载体包裹后得到的植酸素共载纳米乳,具有良好的体外透皮性能、抑菌活性及祛痘控油功效,在祛痘控油护肤品领域有良好的应用前景。 展开更多
关键词 植物水杨酸/苦杏仁酸/壬二酸 共载纳米乳 透皮实验 抑菌活性 祛痘控油
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