Ultra performance liquid chromatography coupled with electrospray and atmospheric pressure chemical ionization (ESCi)-quadrupole time-of-flight mass spectrometry with novel mass spectrometry(Elevated Energy) (MS(E)) data collection technique: determination and pharmacokinetics, tissue distribution and biliary excretion study of ergone in rat

Ergosta-4,6,8(14),22-tetraen-3-one (ergone) has been proved to have novel antitumor effects on HepG2 cells. The aim of this study was to investigate the pharmacokinetics, tissue distribution, and biliary excretion of ergone in rats following a single oral administration (5, 10, and 20 mg/kg). The levels of ergone in plasma, tissues, and bile were measured by ultra performance liquid chromatography coupled with electrospray and atmospheric pressure chemical ionization (ESCi)-quadrupole time-of-flight mass spectrometry with novel mass spectrometry(Elevated Energy) (MS(E)) data collection technique method. The results show ergone was distributed and eliminated from rat plasma and in non-linear pharmacokinetics from a dose range of 5-20 mg/kg. The ergone was found to distribute widely in the internal organs, with tissue concentrations in order of lungs, spleen, liver, intestine, kidneys, heart, stomach, parorchis, teasticles, and brain. At 12 h after dosing, the tissue concentrations in the organs were markedly decreased. The lungs, spleen, and liver were the dominant organs with high tissue concentrations that might be the primary sites for metabolism and elimination of ergone. Total recoveries of ergone within 24 h in bile were 34.14%.     

Determination of Trace Levels of Aluminum in Natural Waters with Rubeanic Acid by Adsorption Chronopotentiometry

A very sensitive and selective analytical method for the determination of trace levels of aluminum in the natural waters is presented in this paper. It is based on the adsorption chronopotentiometry in the presence of rubeanic acid (RA). Complexation of Al by RA is rapid and the procedure of heating sample or waiting is not required.     

反相微乳液法制备膜状普鲁士蓝类配合物纳米材料

在十六烷基三甲基溴化铵(CTAB)/正戊醇/异辛烷/水构成的油包水型(W/O)微乳体系中合成了膜状及50 nm立方状的Co-Fe普鲁士蓝类配合物(cobalt-iron Prussian blue analogues). 研究了w值(水与CTAB的物质的量的比)、反应物浓度和反应温度对产品形貌的影响. 并用原子力显微镜(AFM), 透射电子显微镜(TEM), 电子能谱(EDS), X射线光电子能谱(XPS)和红外(IR)对产品进行了表征.     

27Al核磁共振波谱法测定环境生物样品中铝研究进展

近二十年来,高分辨率²⁷Al核磁共振(²⁷Al NMR)广泛应用于研究Al(Ⅲ)离子水解过程,Al(Ⅲ)与环境生物配体的配位化学,环境与生物样品中铝含量测定和形态分析,监测铝在植物、动物、酵母菌等微生物中的转运过程,具有快速、直接、非破坏性等优点。²⁷Al NMR不仅适用于高浓度的溶液,也可应用于低浓度(10^-6mol·L^-1)的实际环境、生物样品。应用²⁷Al MASNMR可直接对固态样品中铝的存在状态和含量进行表征和测量。本文中对²⁷Al NMR的应用进展作一评述,并总结了近二十年来文献发表的²⁷Al化学位移数据。引用文献70余篇。     

Fermion Coherent State Studies of One-Dimensional Hubbard Model

We present a comparative study of the ground state of the one-dimensional Hubbard model. We first use a new fermion coherent state method in the framework of Fermi liquid theory by introducing a hole operator and considering the interactions of two pairs electrons and holes. We construct the ground state of the Hubbard model as ｜〉=[f＋∑^tφk1σ1hk2σ2ck3σ3hk4σ4 ∏exp（ρck1σ1 hk2σ2）]｜〉0,where φ and ρ are the coupling constants. Our results are then compared to those of varlational methods, density functional theory based on the exact solvable Bethe ansatz solutions, variational Monto-Carlo method （VMC） as well as to the exact result of the infinite system. We find satisfactory agreement between the fermion coherent state scheme and the VMC data, and provide a new picture to deal with the strongly correlated system.     

Identification of Pulsatilla chinensis (Bge.) Regel and look-alike species by UHPLC-TOF-MS using multivariate statistical analysis

Pulsatillae Radix, the root of Pulsatilla chinensis (Bge.) Regel, is recorded in the Pharmacopoeia of the People's Republic of China and has been widely used for its pharmacological activities, such as anti-inflammatory, antioxidant, antibacterial, antitumor, and cardiovascular benefits. However, there are several look-alike species that can be marketed as Pulsatillae Radix. To distinguish P. chinensis (Bge.) Regel from its look-alikes, viz. Pulsatilla cernua (Thunb.) Bercht et Opiz., Pulsatilla dahurica (Fisch.) Spreng., Anemone tomeutosa (Maxim.) Pei., and Rhaponticum uniflorum (L.) DC, we used ultra high performance liquid chromatography with time-of-flight mass spectrometry combined with principal component analysis to compare their chemical compositions. Four ions, a (RT 8.98 min, m/z 1381.6671), b (RT 10.64 min, m/z 1219.6143), c (RT 11.52 min, m/z 1217.5978), and d (RT 13.6 min, m/z 749.4463), from P. chinensis (Bge.) Regel were identified as potential chemical markers to distinguish it from look-alike species using an unsupervised statistical model combined with orthogonal partial least-squares discriminant analysis. The results of this study provide an effective method for identifying and distinguishing P. chinensis (Bge.) Regel from similar plants.     

NaKCoFe普鲁士蓝类配合物纳米颗粒的磁性研究

在2-乙基己基琥珀酸酯磺酸钠(AOT)/异辛烷/水微乳液体系内,通过改变w值(水与AOT的物质的量之比)和反应物浓度比例得到了5nm球形至80nm立方状的NaKCoFe普鲁士蓝类配合物。发现w值和反应物浓度比不仅影响产物的形貌,而且影响配合物的结构。用UV、XRD、EDS、ICP、IR和超导量子干涉仪(SQUID)等对产品进行了结构和磁学性能的表征,发现影响产物磁性的主要因素是碱金属的含量。     

具有p波超流的一维非公度晶格中迁移率边研究

研究了具有p波超流的一维非公度晶格中迁移率边的性质. 发现适当的p波超流可以增加体系中的迁移率边的数目, 并且通过多分形分析确定了迁移率边所在的位置.     

Spectrum Density Factor of Photons and Its Application in the Casimir Forc *

The observables of continuous eigenvalues are defined in an infinite-dimensional ket space. The complete set of such eigenstates demands a spectrum density factor, for example, for the photons in the free space and electrons in the vacuum. From the derivation of the Casimir force without an artificial regulator we determine the explicit expression of the spectrum density factor for the photon field to be an exponential function. The undetermined constant in the function is fixed by the experimental data for the Lamb shift. With that, we predict that there exists a correction to the Casimir force.     

Unveiling the Unique Roles of Metal Coordination and Modulator in the Polymorphism Control of Metal-Organic Frameworks

Polymorphism control of metal-organic frameworks is highly desired for elucidating structure-property relationships, but remains an empirical process and is usually done in a trial-and-error approach. We adopted the rarely used actinide cation Th⁴⁺ and a ditopic linker to construct a series of thorium-organic frameworks (TOFs) with a range of polymorphs. The extraordinary coordination versatility of Th⁴⁺ cations and clusters, coupled with synthetic modulation, gives five distinct phases, wherein the highest degree of interpenetration (threefold) and porosity (75.9 %) of TOFs have been achieved. Notably, the O atom on the capping site of the nine-coordinated Th⁴⁺ cation can function as a bridging unit to interconnect neighboring secondary building units (SBUs), affording topologies that are undocumented for other tetravalent-metal-containing MOFs. Furthermore, for the first time HCOOH has been demonstrated as a bridging unit of SBUs to further induce structural complexity. The resulting TOFs exhibit considerably different adsorption behaviors toward organic dyes, thus suggesting that TOFs represent an exceptional and promising platform for structure-property relationship study.