双冠醚化合物的合成研究 III. 一类新的双冠醚的合成

邻苯二酚、3,5-二叔丁基邻苯二酚分别与1,5-二氯-3-氧(杂)戊烷在碱性条件下反应, 合成了开链冠醚化合物(1a-b)。1a-b与环氧氯丙烷在氢氧化钠正丁醇中缩合, 得到相应的6-羟基二苯并-16-冠-5(2a-b)。化合物2a-b分虽与丁二酰氯、壬二酰氯在无水苯中反应, 生成了两种新的酯型双冠醚化合物3a-b; 2a-b分别与1,3-二溴丙烷、1,4-二溴丁烷、1,5-二溴戊烷、1,8-二氯-3,6-二氧(杂)辛烷及1,11-二氯-3,6,9-三氧(杂)十一烷在无水二氧六环中反应, 得到了四种新的醚型双冠醚化合物4a-e。     

双Sine-Gordon方程的对称和守恒律

通过使用经典李对称方法建立双Sine-Gordon方程的李点对称和LieBcklund对称,并证明此方程是非线性自伴随的.根据双Sine-Gordon方程的对称和它的伴随方程构造它的守恒律.     

基于过硫酸盐活化的微界面电子转移氧化技术

基于过硫酸盐活化的高级氧化技术是当前环境领域的研究热点.然而,环境中广泛存在的基质严重地制约了这一技术的实际应用.最新研究表明,在某些催化剂的作用下,过硫酸盐能够以电子转移的非自由基机制氧化降解污染物,而催化剂主要起电子转移媒介的作用.这一技术不易受水环境中氯离子、碳酸氢根离子等常见阴离子和天然有机物的影响,对目标污染...     

电催化4-喹诺酮和二烃基二硒醚的交叉脱氢偶联反应

发展环境污染少的可持续绿色合成反应是绿色化学的主要目标之一.均相反应是制备高附加值化学品的重要方法,但是该类反应普遍存在催化剂和有机溶剂不易回收利用、产品分离纯化成本高、污染重的问题.发展兼具催化剂和溶剂易循环使用及产品易分离纯化的高附加值化学品的绿色制备方法具有重要的研究意义.4-喹诺酮是一类重要的氮杂环化合物,广泛...     

Heralded path-entangled NOON states generation from a reconfigurable photonic chip

Maximal multi-photon entangled states, known as NOON states, play an essential role in quantum metrology. With the number of photons growing, NOON states are becoming increasingly powerful and advantageous for obtaining supersensitive and super-resolved measurements. In this paper, we propose a universal scheme for generating three- and four-photon path-entangled NOON states on a reconfigurable photonic chip via photons subtracted from pairs and detected by heralding counters. Our method is postselection free, enabling phase supersensitive measurements and sensing at the Heisenberg limit. Our NOON-state generator allows for integration of quantum light sources as well as practical and portable precision phase-related measurements.     

Bright 547-dimensional Hilbert-space entangled resource in 28-pair modes biphoton frequency comb from a reconfigurable silicon microring resonator

High-dimensional entanglement provides valuable resources for quantum technologies,including quantum communication,quantum optical coherence tomography,and quantum computing.Obtaining a high brightness and dimensional entanglement source has significant value.Here we utilize a tunable asymmetric Mach–Zehnder interferometer coupled silicon microring resonator with 100 GHz free spectral range to achieve this goal.With the strategy of the tunable coupler,the dynamical and extensive tuning range of quality factors of the microring can be obtained,and then the biphoton pair generation rate can be optimized.By selecting and characterizing 28 pairs from a more than 30-pair modes biphoton frequency comb,we obtain a Schmidt number of at least 23.4 and on-chip pair generation rate of 19.9 MHz/m W;under a low on-chip pump power,which corresponds to 547 dimensions Hilbert space in frequency freedom.These results will prompt the wide applications of quantum frequency comb and boost the further large density and scalable on-chip quantum information processing.     

深情怀念恩师余先觉教授

1994年8月10日晨,中国遗传学界一颗巨星陨落,我们的恩师,著名的细胞遗传学家余先觉教授逝世。噩耗传来,我们悲痛万分,为遗传学界痛失一位杰出的前辈而惋惜,也为我们痛失一位德高望重的导师而悲怆。缅怀往事,余老的伟岸人格、高尚情操和治学之道将永远铭刻在我们心中。 余先觉先生1909年11月出生于湖南省长沙县,1935年毕业于武汉大学生物学系并留校任教。他先后担任武汉大学校务委员会委员、校学术委员会委员,并曾任中国遗传学会理事,中国细胞生物学会理事、中国遗传学动物遗传委员会委员,《遗传学报》、《遗传》和《水生生物学报》等期刊的编委,并数届连任湖北省遗传学会理事长。 余先觉先生于1946年公费留学,赴美国加州理工学院,在现代遗传学泰斗、诺贝尔奖金获得者摩尔根教授的实验室攻读博士     

自我控制回报的创新性溢价

基于产品创新性之间的选择无差异性,诱导出产品创新性-价格均衡机制,给出作为自我控制回报的创新性溢价,并分析其对资本回报率和规模报酬的影响;进一步分析了创新性溢价对产品创新性分布的影响,并探讨市场最低准入创新性对创新性溢价的影响;最后,分析与比较了自我控制成本变化和动态诱惑下的创新性溢价.给出高创新性产品超额收益率的理论来源,为大规模投资提供了基于均衡的动力机制;同时解释了不同市场间持久存在的产品价格差异,为发展中国家相对较多的山寨与假冒高创新性高质量产品的行为提供了新的分析框架.     

双冠醚化合物的合成研究 III. 一类新的双冠醚的合成

邻苯二酚、3,5-二叔丁基邻苯二酚分别与1,5-二氯-3-氧(杂)戊烷在碱性条件下反应, 合成了开链冠醚化合物(1a-b)。1a-b与环氧氯丙烷在氢氧化钠正丁醇中缩合, 得到相应的6-羟基二苯并-16-冠-5(2a-b)。化合物2a-b分虽与丁二酰氯、壬二酰氯在无水苯中反应, 生成了两种新的酯型双冠醚化合物3a-b; 2a-b分别与1,3-二溴丙烷、1,4-二溴丁烷、1,5-二溴戊烷、1,8-二氯-3,6-二氧(杂)辛烷及1,11-二氯-3,6,9-三氧(杂)十一烷在无水二氧六环中反应, 得到了四种新的醚型双冠醚化合物4a-e。     

Improving the spectral purity of single photons by a single-interferometer-coupled microring

We experimentally engineer a high-spectral-purity single-photon source using a single-interferometer-coupled silicon microring. By the reconfiguration of the interferometer, different coupling conditions can be obtained, corresponding to different quality factors for the pump and signal/idler. The ratio between the quality factor of the pump and signal/idler ranges from 0.29 to 2.57. By constructing the signal—idler joint spectral intensity, we intuitively demonstrate the spectral correlation of the signal and idler. As the ratio between the quality factor of the pump and signal/idler increases, the spectral correlation of the signal and idler decreases, i.e., the spectral purity of the signal/idler photons increases. Furthermore, time-integrated second-order correlation of the signal photons is measured, giving a value up to 94.95±3.46%. Such high-spectral-purity photons will improve the visibility of quantum interference and facilitate the development of on-chip quantum information processing.