Property （ω） and topological uniform descent

We give the necessary and sufficient condition for a bounded linear operator with property （ω） by means of the induced spectrum of topological uniform descent, and investigate the permanence of property （ω） under some commuting perturbations by power finite rank operators. In addition, the theory is exemplified in the case of algebraically paranormal operators.     

Synthesis and Biological Activities of Novel 1,2,4-Triazole Derivatives Containing 1,2,3-Thiadiazole Ring

A series of novel 1,2,4-triazole derivatives containing 1,2,3-thiadiazole ring was designed and synthesized. Their structures were confirmed by IR, 1^H NMR, high resolution mass spectrometer（HRMS） and electrospray ionization-mass spectromcter（ESI-MS） combined with melting points and elemental analysis. Preliminary bioassays indi- cate that these compounds exhibit good insecticidal activity against Aphis laburni at 100 μg/mL, especially compound 6b shows mortality of no less than 95%. Most of the compounds show good activities against tobacco mosaic virus（TMV） with different modes in vivo at 100 μg/mL. Compound 6d standed out, showing a good insecticidal activity and very high induction effects against TMV in vivo. Collectively, our data demonstrate a new strategy for insect and virus control.     

Voltammetric Determination of Epinephrine in the Presence of Uric Acid Based on Aminated Graphene and Ag NPs Hybrid Membrane Modified Electrode

A hybrid membrane consisted of aminated graphene and Ag nanoparticles（Ag NPs） was prepared on the surface of glassy carbon electrode（GCE） by cyclic voltammetry（CV） with aminated graphene（GR-NH2） as matrix for immobilizing Ag NPs.The morphology and electrochemical properties of this hybrid membrane were characterized by scanning electron microscopy（SEM） and CV,respectively,and on this membrane,the voltammetric behaviors of epinephrine（EP） were studied in detail.The membrane exhibited excellent eletro-catalytic activities for the redox of EP,and could resolve the electrochemical response of EP and uric acid（UA） into two oxidation peaks.The peak current of EP was linear with its concentration in the ranges of 0.916-18.3 μmol/L and 18.3-184 μmol/L.The detection limit was 2.0 nmol/L（S/N=3）.The proposed modified electrode retained the advantages of easy fabrication,high sensitivity and good repeatability for the determination of EP.     

Synthesis and Release Behavior of a Hybrid of Camptothecin Intercalated Dodecyl Sulfate Modified Layered Double Hydroxide

The intercalation of a non-ionic and poorly water-soluble drug,camptothecin（CPT）,into dodecyl sulfate （DS） modified layered double hydroxide（LDH） was carried out via a secondary intercalation method to obtain a CPT-DS-LDH hybrid.The in vitro CPT release eFxaminations from the hybrid show that the hybrid can well control the release of CPT,which indicates that the hybrid is a potential drug controlled-release system.Moreover,the intercalation kinetics of CPT into the DS modified LDH fits for the pseudo-second-order model.And the release kinetic process of CPT from the CPT-DS-LDH hybrid at pH=4.8 can be described with pseudo-first-order model,while that at pH=7.2 can be described with both pseudo-first-order model and pseudo-second-order model.Meanwhile,the release mechanism of CPT from the CPT-DS-LDH hybrid was discussed.     

Synthesis,Characterization and Application of Methyl 3,5-Disulfo-benzoate Dipotassium Dihydrate as Nucleating Agent for Poly（L-lactide）

A newly synthesized aromatic sulfonate compound,complex 2 with formula of K2[H3COOC-C6H3（SO3）2]·2H2O（methyl 3,5-disulfo-benzoate dipotassium dihydrate） was synthesized and characterized by elemental analysis,infrared（IR） spectrometry,nuclear magnetic resonance（NMR） and crystal structure measurement.Single-crystal X-ray diffraction（XRD） revealed that complex 2 crystallized in the triclinic system with space group P（i）.Complex 2 was used as nucleating agent for poly（L-lactide）（PLLA）.The crystallization of PLLA with powder of complex 2 was investigated by means of differential scanning calorimetry（DSC） and polarized optical microscopy （POM）.The results prove that complex 2 was effective as nucleating agent for PLLA.It could accelerate crystallization by reducing the induction time and increasing the density of nuclei in the crystallization process.The half-time of crystallization（t0.5） for pure PLLA was about 8 times longer than that of PLLA sample with 1.0％（mass fraction） of complex 2.     

Tunable nano Peltier cooling device from geometric effects using a single graphene nanoribbon

Based on the phenomenon of curvature-induced doping in graphene we propose a class of Peltier cooling devices, produced by geometrical effects, without gating. We show how a graphene nanorib- bon laid on an array of curved nano cylinders can be used to create a targeted and tunable cooling device. Using two different approaches, the Nonequilibrium Green＇s Function （NEGF） method and experimental inputs, we predict that the cooling kW/cm2, on par with the best known techniques power of such a device can approach the order of using standard superlattice structures. The structure proposed here helps pave the way toward designing graphene electronics which use geometry rather than gating to control devices.     

Concentration-dependent crystal structure,elastic constants and electronic structure of Zr x Ti1−x alloys under high pressure

The physical properties of ZrxTi1-x（x=0.0, 0.33, 0.5, 0.67, 0.75 and 1.00） alloys were sinmlated by virtual crystal approximation （VCA） methods which is generally used for disordered solid solutions modeling. The elastic constant, electronic structure and thermal Equation of state （EOS） of disor- dered ZrxTi1-x alloys under pressure are investigated by plane-wave pseudo-potentia1 method. Our simulations reveal increasement of variations of the calculated equilibrium volumes and decrease- ment of Bulk modulus as a function of the alloy compositions. Lattice parameters a and c of alloys with differentZr concentrations decrease linearly with pressure increasing, but the c/avalues are increasing as pressure increases, indicating no phase transitions under pressure from 0 GPa to 100 GPa. The elastic constants and the Bulk modulus to the Shear modulus ratios （B/G） indicate good ductility of Zr, Zr0.33 Ti0.67 Zr0.5Ti0.5, Zr0.75Ti0.25 and Ti, but the Zr0.67Ti0.33 alloy is brittle under 0 K and 0 GPa. The metallic behavior of these alloys was also proved by analyzing partial and total DOS.     

Synthesis and Anti-leukemia Evaluation of Tetrahydro-4H-pyrano[3,2-c]pyridines and Corresponding Anti-CD14 Monoclonal Antibody Conjugates

A series of novel tetrahydro-4H-pyrano[3,2-c]pyridines（3a-3p） were synthesized and found to possess potent antiproliferative activity against leukemia K562 cells in vitro. Preliminary bioassay indicates that compounds 3a and 3e afford the best activity, the IC50 values of them were 6.93 and 7.51μg/mL, respectively, which were lower than that of the anticancer drug 5-FU（1C50=8.56μg/mL）. To reduce the toxicity of compounds 3a-3p to the prolife- ration of normal bematopoietic cells, a tumor targeted CD14 monoclonal antibody（McAb） was used in conjugation with compounds 3a--3p to get conjugates 4a--4p, respectively. The inhibitory activities of conjugates 4a--4p toward K562 cells were discovered to approach those of compounds 3a--3p. In the presence of CD14 McAb, tumor cells were found to be much more susceptible to conjugates 3a--3p than normal hematopoietic cells. Therefore, the toxicity of conjugates 4a--4p to normal hematopoietic cells declined obviously. For example, as for the toxicity of compound 3a compared with that of compound 4a, the value of ICs0 increased from 35.90 μmol/L to 39.52 μmol/L.     

Rapid Quantification of Astilbin in Rat Plasma by Liquid Chromatography-tandem Mass Spectrometry and Its Application to Pharmacokinetic Study

Astilbin is a potential immunosuppressive agent with minor cytotoxicity. Its oral bioavailability is supposed to be rather low and therefore a sensitive analytical method is required for its pharmacokinetic study after oral administration. A simple, sensitive and rapid liquid chromatography-tandem mass spectrometry（LC-MS/MS） method was developed and validated for the determination of astilbin in rat plasma. Plasma samples were subjected to liquid-liquid extraction with ethyl acetate and separated by reversed phase high performance liquid chromatography（HPLC） with methanol-0.01%（volume fraction） formic acid（50：50, volume ratio） as mobile phase. Quantitive determination was achieved on negative LC-MS/MS by a multiple reaction moitoring method with transitions m/z 449.1→150.9（quantifier） and m/z 449.1→284.9（qualifier） for astilbin and m/z 128.9→42.0 for internal standard（IS）. A lower limit of quantification（LLOQ） of ng/mL was achieved within a short cycle time of 3.4 min. The method was successfully applied to a pharmacokinetic study involving oral and intravenous administrations of 6 mg/kg astilbin to six rats.     

同步辐射显微红外光谱研究6-OHDA诱导帕金森病细胞模型

神经毒素6-hydroxydopamine (6-OHDA)处理的人神经瘤母细胞系SH-SY5Y是一种经典的帕金森病细胞模型。利用同步辐射红外显微光谱研究6-OHDA处理的SH-SY5Y细胞系的生物化学成分。与正常细胞相比较,所含磷脂的平均饱和水平显著提高,蛋白质的二级结构发生显著变化,其中的β-sheet的比例明显增高,核酸的含量明显下降,提示神经毒素6-OHDA对细胞造成了严重的氧化损伤。同步辐射红外显微光谱能够精确有效的检测到细胞生化成分的改变,从而对细胞的病理损伤进行评估。