TiO_2/CuPc/NiFe-LDH photoanode for efficient photoelectrochemical water splitting

Photoelectrochemical(PEC) water splitting is a promising approach for renewable hydrogen production.However,the practical PEC solar-to-fuel conversion efficiency is still low owing to poor light absorption and rapid recombination of charge carriers in photoelectrode.In this work,we report a ternary photoanode with simultaneously enhancement of light absorption and water oxidation efficiency by introducing copper phthalocyanine(CuPc) and nickel iron-laye red double hydroxide(NiFe-LDH) on TiO_2(denoted as TiO_2/CuPc/NiFe-LDH).An experimental study reveals that CuPc loading on TiO_2 bring strong visible light absorption;NiFe-LDH as an oxygen evolution reaction catalyst efficiently accelerates the surface water oxidation reaction.This synergistic effect of CuPc and NiFe-LDH gives enhanced photocurrent density(2.10 mA/cm2 at 0.6 V vs.SCE) and excellent stability in the ternary TiO_2/CuPc/NiFeLDH photoanode.     

A time-dependent density functional theory investigation of the spectroscopic properties of the beta-subunit in C-phycocyanin

By using time-dependent density functional theory combined with the polarizable continuum model, a satisfactory assignment of the absorption and circular dichroism spectra and energy transfer flow of the beta-subunit in C-phycocyanin (C-PC) was achieved when the protonation of beta-84 and beta-155 phycocyanobilin (PCB) and their interaction with the protein moiety in C-PC have been taken into account. We attribute the main peak for both beta-84 and beta-155 as arising from the pi electron excitation of the pyrrole rings and the shoulder peak as arising from the charge transfer from the asparate residue to PCBH(+). The satisfactory agreement between theory and experiment suggests that F?rster resonance theory prevails such that energy transfer occurs from beta(s) (beta-155) to beta(f) (beta-84).     

Catalyst‐Controlled Stereoselective Olefin Metathesis as a Principal Strategy in Multistep Synthesis Design: A Concise Route to (+)‐Neopeltolide

Molybdenum‐, tungsten‐, and ruthenium‐based complexes that control the stereochemical outcome of olefin metathesis reactions have been recently introduced. However, the complementary nature of these systems through their combined use in multistep complex molecule synthesis has not been illustrated. A concise diastereo‐ and enantioselective route that furnishes the anti‐proliferative natural product neopeltolide is now disclosed. Catalytic transformations are employed to address every stereochemical issue. Among the featured processes are an enantioselective ring‐opening/cross‐metathesis promoted by a Mo monoaryloxide pyrrolide (MAP) complex and a macrocyclic ring‐closing metathesis that affords a trisubstituted alkene and is catalyzed by a Mo bis(aryloxide) species. Furthermore, Z‐selective cross‐metathesis reactions, facilitated by Mo and Ru complexes, have been employed in the stereoselective synthesis of the acyclic dienyl moiety of the target molecule.     

硫代氨基甲酸酯合成方法进展

硫代氨基甲酸酯是一类分子内含有多种官能团的化合物,大多数具有生物活性,在医学、生物、农药等方面有广泛的应用.本文总结了合成硫代氨基甲酸酯的几种主要方法,如水解醇解法、重排反应、光气衍生物法、羰基化法等,并分析了各种方法的利弊.指出利用一氧化碳进行硒催化的硫醇与硝基化合物或苯胺的羰基化反应来合成硫代氨基甲酸酯是一种比较有应用前景的方法.该方法具有环境友好、原子经济性高、步骤简短等优点,并对其做了比较详细的介绍.     

希土胺羧酸配合物的研究——Ⅲ.吡啶-2,6-二甲酸钕配合物{[Nd(HDPA)(DPA)(H2O)2]·4H2O}n合成及其晶体结构

关于吡啶-2,6-二甲酸希土配合物晶体结构有Na₃[Ln(DPA)₃]·yNaClO₄·xH₂O类型的报道^[1]。本文合成了{[Nd(HDPA)(DPA)(H₂O)₂]·4H₂O}_n。配合物单晶并测定了其结构。     

An electrochemically prepared sky-blue light emitting ether functionalized polyfluorene as chemosensor for metal ions

Synthesis and electrochemical polymerization of 9,9-bis(2-(2-(2-methoxy ethoxy)ethoxy)ethyl)-fluorene(EO-F)into poly[9,9-bis(2-(2-(2-methoxy ethoxy)ethoxy)ethyl)-fluorene](EO-PF) films are reported. The boron trifluoride diethyl etherate electrolyte enables facile preparation of EO-PF films at lower potential compared to LiClO4/MeCN and the electrochemical polymerizations are discussed. The EO-PF shows good electrochemical behavior and can be dissolved in solvents such as DMSO and THF. The solubility of EO-PF in THF is 2 mg mL 1and the number average molecular weight is35300 with a polydispersity index of 1.65. The side chains on C9position of the monomer maintain unchanged after electrooxidation into corresponding polymer. The EO-PF dissolved in THF under 365 nm ultraviolet light is sky blue light emitting with the Commission Internationale de L Eclairage-CIE coordinates of(0.19, 0.15). The electropolymerized EO-PF is used for the first time in chemosensing metal ions, demonstrating fluorescence quenching for Mn2+and Fe3+while fluorescence enhancement for Cr6+ions.     

通过大分子单体的“点击”反应合成超支化聚苯乙烯

用一端带有一个叠氮基,另一端带有两个炔基的聚苯乙烯(PSt)大分子单体,通过"点击"化学反应,成功制备了结构规整的超支化聚苯乙烯。首先,L-天冬氨酸经过溴化和酯化两步反应得到含有两个炔基的原子转移自由基聚合(ATRP)引发剂——2-溴代琥珀酸双炔丙基酯(BPBS),然后引发苯乙烯的ATRP,并通过NaN3的取代反应把末端溴转化为叠氮基,得到AB2型大分子单体(CH≡C)2-PS-N3。这种大分子单体通过"点击"反应聚合得到超支化聚苯乙烯,根据多角度激光光散射(MALLS)测试结果,最终产物重均聚合度DPw可达53,分子量分布Mw/Mn=1.53。     

基于熵的投资组合模糊优化模型

本文对基于信息熵的证券投资组合模型，根据模糊决策理论，在模糊环境下对模型进行求解，将投资者的主观意见反映在模糊情况的组合投资模型中，并通过实例，验证了该模型解法的可行性和有效性。     

Determination of faropenem in human plasma and urine by liquid chromatography-tandem mass spectrometry

A simple, rapid and sensitive liquid chromatography/electrospray tandem mass spectrometry (LC-MS/MS) quantitative detection method, using cefalexin as internal standard, was developed for the analysis of faropenem in human plasma and urine. After precipitation of the plasma proteins with acetonitrile, the analytes were separated on a C18 reversed-phase column with 0.1% formic acid-methanol (45:55, v/v) and detected by electrospray ionization mass spectrometry in positive multiple reaction monitoring mode. Calibration curves with good linearities (r=0.9991 for plasma sample and r=0.9993 for urine sample) were obtained in the range 5-4000 ng/mL for faropenem. The limit of detection was 5 ng/mL. Recoveries were around 90% for the extraction from human plasma, and good precision and accuracy were achieved. This method is feasible for the evaluation of pharmacokinetic profiles of faropenem in humans, and to our knowledge, it is the first time the pharmacokinetic of faropenem has been elucidated in vivo using LC-MS/MS.     

Enhancing the thermoelectric performance through the mutual interaction between conjugated polyelectrolytes and single-walled carbon nanotubes

We present a method of constructing composites composed of conjugated polyelectrolytes(CPEs)and singlewalled carbon nanotubes(SWCNTs)to obtain a high-performing flexible thermoelectric generator.In this approach,three kinds of polymers,namely,poly[(1,4-(2,5-didodecyloxybenzene)-alt-2,5-thiophene](P1),poly[(1,4-(2,5-bis-sodium butoxysulfonate-phenylene)-alt-2,5-thiophene](P2),and poly[(1,4-(2,5-bis-acid butoxysulfonic-phenylene)-alt-2,5-thiophene](P3)are designed,synthesized and complexed with SWCNTs as thermoelectric composites.The electrical conductivities of the CPEs/SWCNTs(P2/SWCNTs,and P3/SWCNTs)nanocomposites are much higher than those of non-CPEs/SWCNTs(P1/SWCNTs)nanocomposites.Among them,the electrical conductivity of P2/SWCNTs with a ratio of 1:4 reaches 3686 S·cm^-1,which is 12.4 times that of P1/SWCNTs at the same SWCNT mass ratio.Moreover,CPEs/SWCNTs composites(P2/SWCNTs)display remarkably improved thermoelectric properties with the highest power factor(PF)of 163μW·m^-1·K^-1.In addition,a thermoelectric generator is fabricated with P2/SWCNTs composite films,and the output power and power density of this generator reach 1.37μW and 1.4 W·m;(cross-section)at△T=70 K.This result is over three times that of the thermoelectric generator composed of non-CPEs/SWCNTs composite films(P1/SWCNTs,0.37μW).The remarkably improved electrical conductivities and thermoelectric properties of the CPEs/SWCNTs composites(P2/SWCNTs)are attributed to the enhanced interaction.This method for constructing CPEs/SWCNTs composites can be applied to produce thermoelectric materials and devices.