Continuous weak measurement and feedback control of a solid-state charge qubit: A physical unravelling of non-Lindblad master equation

Conventional quantum trajectory theory developed in quantum optics is largely based on the physical unravelling of a Lindblad-type master equation, which constitutes the theoretical basis of continuous quantum measurement and feedback control. In this work, in the context of continuous quantum measurement and feedback control of a solid-state charge qubit, we present a physical unravelling scheme of a non-Lindblad-type master equation. Self-consistency and numerical efficiency are well demonstrated. In particular, the control effect is manifested in the detector noise spectrum, and the effect of measurement voltage is discussed.

Real-time counting of single electron tunneling through a T-shaped double quantum dot system

Real-time detection of single electron tunneling through a T-shaped double quantum dot is simulated, based on a Monte Carlo scheme. The double dot is embedded in a dissipative environment and the presence of electrons on the double dot is detected with a nearby quantum point contact. We demonstrate directly the bunching behavior in electron transport, which leads eventually to a super-Poissonian noise. Particularly, in the context of full counting statistics, we investigate the essential difference between the dephasing mechanisms induced by the quantum point contact detection and the coupling to the external phonon bath. A number of intriguing noise features associated with various transport mechanisms are revealed.

绵参和地榆的化学成分研究

本论文由三章组成。第一章为综述，概述了植物中环烯醚萜类化合物的研究进展；第二和第三章为实验论文，分别报道了唇形科药用植物绵参和蔷薇科药用植物地榆的化学成分研究。 第一章概述了植物中环烯醚萜类化合物的研究成果，主要包括结构类型及药理活性等方面。 第二章包括两个部分。第一部分报道了藏药绵参（Eriophyton wallichii Benth）地上部分甲醇提取物的化学成分。采用正、反相硅胶柱层析等各种分离方法，从中共分离出7个化合物，有6个化合物为首次从该植物中分离得到，分别为β-谷甾醇（1），夏至草苦素（marrubiin，2），乌苏酸（3），cimigoside（4），5-deoxyantirrhinoside（5），8-表马钱子酸葡萄糖苷（8-epiloganic acid，6）和apigenin 7-(6''-p-coumaroyl)glucoside（7）。第二部分，采用高效液相色谱－质谱联用技术对绵参地上部分的甲醇提取物进行了分析，通过标准品对照紫、外光谱分析以及多级质谱分析与文献对照鉴定了8个成分，分别是：8-epiloganic acid（Ⅰ），quercitrin 3-glucoside-7-(6''-p-coumaroyl)glucoside（Ⅱ），ajugoside(I) （Ⅲ），chrysoeriol 7-O-E-p-coumaroyl-3-O-b-D-glucoside（Ⅳ），helichrysoside（Ⅴ），生物碱（Ⅵ），apigenin 2,3-dihydrogen-7-(6''-p-coumaroyl) glucoside（Ⅶ），apigenin 7-(6''-p-coumaroyl) glucoside（Ⅷ）。 第三章报道了中药地榆根部乙醇提取物正丁醇相的化学成分，通过正、反相硅胶柱层析等各种分离方法，从中分离得到8个化合物，分别为3,4¢- O-二甲基逆没食子酸（8），3,3¢,4¢-O-三甲基逆没食子酸（9）和3,4¢-O-二甲基逆没食子酸-4-O-b-D-木糖苷（10），19a-羟基-3-O-(a-L-阿拉伯糖)乌苏酸-28-O-b-D-葡萄糖苷（11）， 3b-[(a-L-arabinopyranosyl)oxy]-urs-11,13(18)-dien-28-oic acid b-D- glucopyranosyl ester（13），3-O-a-L-arabinopyranosyl-urs-12,18(19)-dien-28-oic acid b-D-glucopyranosyl ester（14），儿茶素（15），还有一种可能是皂苷11的工作产物（12）。 This dissertation consisted of three chapters. The first chapter elaborated the progress of iridoids occurring in plants. The later two chapters respectively elaborated the chemical constituents of Eriophyton wallichii Benth. and Sanguisorba officinalis L. The first chapter is a review of the research progress of iridoids occurring in plants, which includes their structure and pharmacology. The second chapter consisted of two parts. The first part is about the chemical constituents of methanol extraction from the aerial parts of Eriophyton wallichii Benth. Seven compounds were isolated and identified. Among them, the compounds of marrubiin, ursolic acid, cimigoside, 5-deoxyantirrhinoside, 8-epiloganic acid，apigenin 7-(6''-p-coumaroyl)glucoside were firstly reported in this plant. A HPLC-MSn method was developed for rapid identification of major compounds of Eriophyton wallichii. A total of 8 peaks in the chromatograms were unequivocally determined (peaks 1, 8) or tentatively identified (peaks 2-7) based on the detailed UV and tandem mass spectra analysis. Seven components were identified as 8-epiloganic acid（Ⅰ），Quercitrin 3-glucoside-7-(6''-p-coumaroyl)glucoside（Ⅱ），ajugoside(I)（Ⅲ），Chrysoeriol 7-O-E-p-coumaroyl-3-O-b-D-glucoside（Ⅳ），helichrysoside（Ⅴ），apigenin 2,3-dihydrogen-7-(6''-p-coumaroyl) glucoside（Ⅵ），apigenin 7-(6''-p-coumaroyl) glucoside（Ⅶ）。 The third chapter elaborated the chemical constituents of methanol extraction from Sanguisorba officinalis L, eight compounds were isolated from this plant by repeat column chromatography over silica gel. These compounds were identified as 3,4′-O-dimethylellagic acid, 3,3′,4′-O-trimethylellagic acid, 3,4′-O-dimethylellagic acid-4-O-b-D-xyloside, 3b-O-a-L-arabinopyranosyl-19a- hydroxyl-urs-12-en-28-oic acid 28-b-D-glucopyranoside, 3b-[(a-L-arabinopyranosyl)oxy]-urs-11,13(18)-dien- 28-oic acid b-D-glucopyranosyl ester，3-O-a-L–arabinopyranosyl-urs-12,18(19) -dien-28-oic acid b-D-glucopyranosyl ester, catechin.

厚朴中α-葡萄糖苷酶抑制活性成分研究

本论文由三章组成。 第一章是关于厚朴中具有α-葡萄糖苷酶抑制活性成分的研究。凹叶厚朴的乙醇提取物显示了较强的α-葡萄糖苷酶抑制活性。为了确定其活性成分，在活性测试的指导下，通过溶剂萃取、树脂吸附和反复硅胶柱层析等分离方法从凹叶厚朴乙醇提取物中分离得到6 个生物碱，并用质谱和核磁共振等波谱方法分别鉴定为：木兰箭毒碱，木兰花碱，鹅掌楸碱，蕃荔枝碱，罗默碱和Lysicamine。应用小肠α-葡萄糖苷酶模型测定了它们对α-葡萄糖苷酶的抑制作用。其中，番荔枝碱和木兰箭毒碱对α-葡萄糖苷酶相对抑制活性最好，分别为60%和62%；其它四个生物碱成分对α-葡萄糖苷酶的抑制活性几乎相当，鹅掌楸碱为46%，罗默碱为51%，Lysicamine 为49%，木兰花碱为51%。 第二章报道了厚朴酚的衍生物及其对α-葡萄糖苷酶的抑制活性。根据糖苷酶抑制剂的结构特点，设计合成了一系列厚朴酚的衍生物。厚朴酚经过Mannich 反应和环氧化及开环反应制备了一系列衍生物，经活性测试发现衍生物活性与取代基关系较大，其中5,5′-diallyl-3-((bis(2-hydroxyethyl)amino)methyl)biphenyl-2,2′-diol 的抑制活性最高，为72%。 第三章综述了厚朴的化学成分及药理活性两个方面的研究进展。 The dissertation consists of three chapters. The first chapter is about the study on the constituents with α-glycosidase inhibitory activity from Magnolia officinalis. The EtOH extracts of M. officinalis Rehd. et Wils showed good inhibitory activity against α-Glucosidase. In order to determine the active compounds, bio-assay was used to guide the isolation. Six known alkaloids were isolated by solvent extraction and repeated silica gel column chromatography, and their structures were identified as liriodenine, anonaine, roemerine, lysicamine, magnoflorine and magnocurarine by spectroscopic methods. The inhibitory activity against α-Glucosidase of these alkaloids was measured with alvine screening model of α-glucosidase. Among them, lysicamine and liriodenine have the best inhibitory activity at 60% and 62%, respectively. The other four alkaloids have close inhibitory activity, from 46% to 51%. The second chapter is about the derivation of magnolol and the inhibitory a ctivity of the derivatives. Seven derivatives of magnolol were prepared by Manni-ch reaction, epoxidation followed by ring-opening reaction. Biological activity as say indicated the inhibitory activity was related to substituting groups. Among them, 5,5′-diallyl-3-((bis(2-hydroxyethyl)amino)methyl)biphenyl-2,2′-diol had the highest activity at 72%. The third chapter is a review on the progress of M. officinalis including chemical constituents and pharmacological activity.

Studies on the components of crude and processed Fructus Corni by ESI-MSn

The components of crude and processed Fructus Corni were investigated by means of electrospray ionization-tandem mass spectrometry(ESI-MSn) technique in the negative ion mode. Compared with those of crude Fructus Corni, the chemical components of the processed Fructus Corni were changed both in quality and in quantity. From the ESI-MS spectra of the crude and processed Fructus Corni, six peaks were selected to establish the characteristic ESI-MS peaks. Several factors in the processing procedure were examined.

Real-time PCR microfluidic devices with concurrent electrochemical detection

Electrochemistry-based detection methods hold great potential towards development of hand-held nucleic-acid analyses instruments. In this work, we demonstrate the implementation of in situ electrochemical (EC) detection method in a microfluidic flow-through EC-qPCR (FTEC-qPCR) device, where both the amplification of the target nucleic-acid sequence and subsequent EC detection of the PCR amplicon are realized simultaneously at selected PCR cycles in the same device. The FTEC-qPCR device utilizes methylene blue (MB), an electroactive DNA intercalator, for electrochemical signal measurements in the presence of PCR reagent components. Our EC detection method is advantageous, when compared to other existing EC methods for PCR amplicon analysis, since FTEC-qPCR does not require probe-modified electrodes, or asymmetric PCR, or solid-phase PCR. Key technical issues related to surface passivation, electrochemical measurement, PCR inhibition by metal electrode, bubble-free PCR, were investigated. By controlling the concentration of MB and the exposure of PCR mixture to the bare metal electrode, we successfully demonstrated electrochemical measurement of MB in solution-phase, symmetric PCR by amplifying a fragment of lambda phage DNA.