Complementary relation between quantum entanglement and entropic uncertainty

Quantum entanglement is regarded as one of the core concepts,which is used to describe the nonclassical correlation between subsystems,and entropic uncertainty relation plays a vital role in quantum precision measurement.It is well known that entanglement of formation can be expressed by von Neumann entropy of subsystems for arbitrary pure states.An interesting question is naturally raised:is there any intrinsic correlation between the entropic uncertainty relation and quantum entanglement?Or if the relation can be applied to estimate the entanglement.In this work,we focus on exploring the complementary relation between quantum entanglement and the entropic uncertainty relation.The results show that there exists an inequality relation between both of them for an arbitrary two-qubit system,and specifically the larger uncertainty will induce the weaker entanglement of the probed system,and vice versa.Besides,we use randomly generated states as illustrations to verify our results.Therefore,we claim that our observations might offer and support the validity of using the entropy uncertainty relation to estimate quantum entanglement.     

Synthesizing Red Fluorescent Carbon Dots from Rigid Polycyclic Conjugated Molecules: Dual-Mode Sensing and Bioimaging in Biochemical Applications

Red fluorescent carbon dots (R-CDs) are special desirable for biochemical analysis due to good biological compatibility and deep penetration; however, they remain as bottlenecks due to difficulties in expanding the sp² domain, especially those are fused from rigid polycyclic conjugated molecules (RPCMs) with heteroatom substituents due to huge steric hindrance and heteroatom blockage toward graphic lattice. Here, an RPCM with heteroatom substituents, 1,5-diamino-4,8-dihydroxyanthraquinone (DDAQ), based self-doped R-CDs with PL emission at 635 nm is reported. Further investigations reveal that the expanding, hybrid sp² domain with indanthrone tannin structure from DDAQ is mainly responsible for the obtained red fluorescence of R-CDs. Taking advantage of optical properties, R-CDs are considered to construct a colorimetric/fluorescent dual mode sensing array for quantifying trace levels of Fe³⁺ and glyphosate based on the static quenching, and a biomarker for cell imaging. The CD-based sensors exhibit outstanding recovery, high selectivity, and sensitivity, also facilitated dual-mode detection with the naked-eye. The R-CDs have low cytotoxicity, good cell membrane penetration for rapid cell entry, and high resolution, demonstrating their potential for biolabeling and bioanalytic applications.     

Antimicrobial activity of collagen material with thymol addition for potential application as wound dressing

Recently, special attention has been paid to the development of active wound dressing materials based on biopolymers. Collagen is a natural polymer, which meets the requirements of modern materials for medical applications. However, despite its unique properties, collagen has no antimicrobial activity. In this work thymol was incorporated into collagen films to meet antimicrobial properties of the material. Thymol is a naturally occurring phenolic compound recognized as an antimicrobial agent. Collagen/thymol thin films were obtained through solvent evaporation using collagen solutions containing different amounts of thymol. The structure of the obtained materials was studied using FTIR-ATR spectroscopy. The inhibition ability on the growth of several strains of microorganisms was tested. The standard ISO 22196:2007 was used to define the bactericidal properties of the material. The growth of the following bacteria on the collagen/thymol films was studied: Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis, Enterobacter aerogenes, Candida albicans. The results showed that the growth of Staphylococcus aureus was the most inhibited compared to the other tested strains. Collagen/thymol material is more efficient against pathogens through direct contact compared to the diffusion of thymol from the material. In general, the thymol addition inhibits biofilm formation on the collagen surface.     

Flow-injection determination of hydrogen peroxide based on fluorescence quenching of chromotropic acid catalyzed with Fe(II)

Flow-injection analysis system (FIA system), which was based on Fe(II)-catalyzed oxidation of chromotropic acid with hydrogen peroxide, was developed for the determination of hydrogen peroxide. The chromotropic acid has a fluorescence measured at λ_em = 440 nm (emission wavelength) with λ_ex = 235 nm (excitation wavelength), and the fluorescence intensity at λ_em = 440 nm quietly decreased in the presence of hydrogen peroxide and Fe(II), which was caused by Fe(II)-catalyzed oxidation of chromotropic acid with hydrogen peroxide. By measuring the difference of fluorescence intensity, hydrogen peroxide (1.0 × 10⁻⁸-1.0 × 10⁻³ mol L⁻¹) could be determined by the proposed FIA system, whose analytical throughput was 40 samples h⁻¹. The relative standard deviation (RSD) was 1.03% (n = 10) for 4.0 × 10⁻⁸ mol L⁻¹ hydrogen peroxide. The proposed FIA technique could be applied to the determination of hydrogen peroxide in rain water samples.     

Synthesis and characterization of novel spirooxazacamphorsultam derivatives

Derivatives of camphorsultam which contain novel spirooxazolidine and spirooxazine structures have been prepared in high yield and purity. Though it was expected that the ketone moiety would undergo acetal formation, the imine instead underwent reaction and was proven by X-ray crystallography and 2D NMR techniques. The initial ketone-containing derivatives were then reduced to produce exo-hydroxy analogs that have potential as a new family of chiral auxiliaries.     

From a Network of Computed Reaction Enthalpies to Atom‐Based Thermochemistry (NEAT)

A simple and fast, weighted, linear least‐squares refinement protocol and code is presented for inverting the information contained in a network of quantum chemically computed 0 K reaction enthalpies. This inversion yields internally consistent 0 K enthalpies of formation for the species of the network. The refinement takes advantage of the fact that the accuracy of computed enthalpies depends strongly on the quantum‐chemical protocol employed for their determination. Different protocols suffer from different sources of error; thus, the reaction enthalpies computed by them have “random” residual errors. Since it is much more natural for quantum‐chemical energy and enthalpy results, including reaction enthalpies, to be based on the electronic ground states of the atoms and not on the historically preferred elemental states, and since these two possible protocols can be converted into each other straightforwardly, it is proposed that first‐principles thermochemistry should employ the ground electronic states of atoms. In this scheme, called atom‐based thermochemistry (AT), the enthalpy of formation of a gaseous compound corresponds simply to the total atomization energy of the species; it is always positive, and it reflects the bonding strength within the molecule. The inversion protocol developed and based on AT is termed NEAT, which represents the fact that the protocol proceeds from a network of computed reaction enthalpies toward atom‐based thermochemistry, most directly to atom‐based enthalpies of formation. After assembling a database that consisted of 361 ab initio reactions and reaction enthalpies involving 188 species, collected from 31 literature sources, the following dependable 0 K atom‐based enthalpies of formation, Δ_f${H{{{\rm AT}\hfill \atop 0\hfill}}}$ , all in kJ mol^?1, have been obtained by means of NEAT: H₂=432.07(0), CH=334.61(15), NH=327.69(25), OH=425.93(21), HF=566.13(31), CO=1072.08(28), O₂=493.51(34), CH₂=752.40(21), H₂O=918.05(20), HO₂=694.53(32), CO₂=1597.77(40), CH₃=1209.64(29), NH₃=1157.44(33), C₂H₂=1625.78(40), and CH₄=1641.68(40), in which the uncertainty values given in parentheses represent 95 % confidence intervals. The average deviation of these values from the well‐established active thermochemical tables (ATcT) values is a mere 0.25 kJ mol^?1, with a maximum deviation of 0.7 kJ mol^?1. This shows that the use of a large number of ab initio reaction enthalpies within a NEAT‐type protocol has considerable advantages over the sequential utilization of the ab initio information.     

硝酸处理的活性碳催化苯一步合成苯酚

将市售的煤质活性炭用不同浓度的硝酸处理后,在乙腈体系下催化苯一步羟化成苯酚. 并对处理过的活性炭进行Boehm滴定、XPS/EDX、BET等方法表征,发现活性炭表面羧基的数量是影响其催化活性的主要因素. 得到苯酚的最高收率为15.7%,选择性为87.2%.     

N9H9链状异构体的结构与稳定性的理论研究

采用密度泛函理论(DFT)B3LYP方法,在6-311＋＋G**基组水平上对N9H9可能存在的链状构型进行了几何优化,得到46种稳定链状异构体。应用自然键轨道理论NBO和分子中的原子理论AIM分析了这些化合物的成键特征和相对稳定性,G3MP2方法计算了各异构体的精确能量及在298K时的生成热ΔfHө(298K),并计算了由Peter Politzer等人所介绍的相对比冲量。研究结果表明：各异构体中N原子孤对电子与N＝N形成了p→π共轭作用是影响双键相邻的N－N键长变化的主要原因,并且对异构体的稳定性起着重要作用。所有异构体中N＝N位于链端的稳定性较差,其中B9最稳定, B6稳定性最差;C5是所有异构体中生成热最大的,也是相对比冲量最大的。     

小尺寸矩形槽道内气泡生长及运动特性

通过实验研究了液体流动条件下小尺寸矩形槽道底部由微孔注入的气泡生长及运动特性。结合RCD算法与形心提取算法,有效地跟踪了气泡生长及运动轨迹。实验结果表明:气泡的形成过程可分为生长和涌入两个阶段;随着气体流量的增大,后续小气泡的涌入加强,涌入持续时间更长,气泡形成时间增加,等待时间缩短;槽道中小气泡的堆积现象随气体流量的增大而愈加明显。