HPLC-DAD–MS Analysis of Anthocyanins in Rose Wine Made From cv. Öküzgözü Grapes,and Effect of Maceration Time on Anthocyanin Content

The anthocyanin composition of rose wine made from cv. Öküzgözü, a variety of grape native to Turkey, and the effect of maceration time (3, 6, 12, 18, or 24 h) on the anthocyanin content of the wine have been investigated. High-performance liquid chromatography with diode-array detection (HPLC-DAD) and mass spectrometry (MS) were used for anthocyanin analysis. Thirteen different anthocyanins, including five glucosides, five acetyl glucosides, and three coumaroyl glucosides were identified and quantified. It was found that an important characteristic of Öküzgözü rose wine was the presence of a large amount of malvidin-3-glucoside and its acylated esters. The total anthocyanin content of the wine increased with increasing maceration time. On the basis of sensory analysis, the most preferred wine was that produced with 3-h maceration, because of its better color and general flavor attributes.     

Dialing in color with rare earth metals: facile photoluminescent production of true white light

Combining polymeric architectures with metal ions produces hybrid materials with extremely rich properties. We are studying polymers containing terpyridine in the side chain. In this report, the chelation of lanthanide ions, Eu³⁺, Tb³⁺, and Dy³⁺ resulted in metal functionalized copolymers that exhibited excellent emission of red, green, and blue light respectively. The polymer architecture easily allows incorporation of all three colors into the material, which leads to the facile production of true white light in solution or the solid state. Quantum efficiencies for the polymer systems were determined. The white light system had an efficiency of 5%. Various combinations of colors were achieved from the basic RBG colors by simply varying the metal ion ratios in the polymer backbone. This easy tuning of the color makes these systems attractive. Copyright © 2007 John Wiley & Sons, Ltd.     

助熔剂对Y3Al5O12：Ce荧光粉性能的影响

在还原气氛下采用高温固相反应法合成了白光LED用黄色荧光粉Y3Al5O12:Ce(YAG:Ce)研究了助熔剂对YAG：Ce荧光粉发光特性的影响，。XRD的测量结果表明加入合适的助熔剂有利于YAG:Ce荧光粉的晶化，并且不引入杂相，选择BaF2和H3BO3同时使用效果要好于单独使用一种助熔剂，助熔剂的加入可增大YAG：Ce荧光粉的激发和发射光谱强度，并能有效降低荧光粉的中心粒径（D50）控制粉体的粒径分布，适用于白光LED的制造。     

The influence of the sacrificial anode nature on the mechanism of electrochemical arylation and alkylation of white phosphorus

The material of the sacrificial anode has a substantial effect on the nature and yield of the target products of electrochemical phosphorylation of organic halides by white phosphorus in the presence of the nickel complexes with 2,2"-bipyridine. The use of the zinc anode results in the products with tricoordinated phosphorus, viz., triorganylphosphines, the reaction on the aluminum anode affords triorganylphosphine oxides, and the presence of Mg²⁺ ions in the reaction mixture provides the transformation of white phosphorus into cyclic phosphines (PhP)₅.     

Simultaneous determination of carbohydrates and organic acids in beer and wine by ion chromatography

The simultaneous determination of mono-organic acids and carbohydrates by ion chromatography with both conductometric and pulsed amperometric detection is described. The carbohydrates, such as mannitol, arabinose, glucose, fructose, lactose, sucrose, raffinose, and maltose, as well as monoorganic acids including acetate, glycolate, formate, pyruvate, and fluoride are separated as anions by ion-exchange chromatography with 0.080 mol/L sodium hydroxide eluent at 1 mL/min within 12 min. Carbohydrates are determined by pulsed amperometric detection and mono-organic acids are determined by suppressed conductivity detection. The species in beverages are determined.     

Studies on Aggregation Interaction between Reduced Denatured Egg White Lysozymes during Refolding Procedure in Urea Solution

The aggregation interaction between reduced-denatured egg white lysozymes during refolding procedure in urea solution was studied by means of reducing and non-reducing protein electrophoreses. Results of non-reducing sodium dodecyl sulphate polyacrylamide gel electrophoresis （SDS-PAGE） of the supernatant and aggregate precipitate formed in refolding process show that except being refolded to native egg white lysozymes, the reduced-denatured lysozymes can also form the aggregates with molecular weights （MW） being separately about 30.0 and 35.0 kD, while the reducing SDS-PAGE and the refolding results in the presence of sodium dodecyl sulphate show that these aggregates are formed chiefly through the misconnection of disulfide bonds between the reduced-denatured lysozymes, and the aggregate precipitates are formed through the non-covalent interactions between the aggregates with molecular weight being about 30.0 kD. From the results of electrophoresis and size-exclusion chromatographic analyses, it can be inferred that the aggregates with molecular weights being about 30.0 and 35.0 kD are bi-molecular and tri-molecular egg white lysozyme aggregates, respectively. And finally, a suggested refolding mechanism of reduced-denatured egg white lysozymes in urea solution was presented.     

Electrochemical synthesis of phosphorus esters from white phosphorus in the presence of copper complexes and ethanol

In the presence of white phosphorus the redox potentials of the copper ions change and the potential of the reduction wave of Cu^I/Cu⁰ shifts noticeably toward more positive values. The Cu^I—P₄ complex is characterized by a lower value of the electrochemical gap, that is, higher polarizability and reactivity compared to those of the free Cu^I cation. Phosphorus esters can be synthesized from P₄ and ethanol. The latter is in the composition of the copper(ii) complexes, which act as a catalyst-charge mediator.     

Covalent Structures of Phosphorus: A Comprehensive Theoretical Study

Starting from earlier work by Baudler we introduce a chemical heuristic for the systematic deduction and classification of covalent partial structures of phosphorus in polycyclic phosphanes, phosphorus-rich polycyclic phosphides, and allotropes of phosphorus except the black forms. This approach is used to direct ab initio techniques (which also confirm the rules) in the quest for as yet unknown forms of molecular or macromolecular phosphorus. Based on calculated stabilities of systematically generated structural alternatives we rationalize the stabilities of Hittorf's phosphorus and of molecular P₄, confirm the possible existence of at least one other crystalline allotropic form of phosphorus, and provide insight into the probable structure of amorphous red phosphorus. In total, the combined approach of chemical heuristics and large scale ab initio calculations presented in this work supplies a coherent chemical understanding of covalent polyphosphorus structures.     

白钨酸研究——Ⅶ.K3W2Cl9的制备及反应

用粉状白钨酸作原针,在一般条件下制备K₃W₂Cl₉,产率达53%,证明白钨酸是比黄钨酸优越的钨化学试剂。研究了K₃W₂Cl₉经离子又换转化为酸的形态后与Ndz₂(C0₃)₃的反应。得到了新的化合物NdW₂Cl₉,提出了一条新的制备溶解度大的各种金属离子与W₂Cl₉^3-的化合物的途径。 对K₃W₂Cl₉和NdW₂Cl₉进行了紫外可见尤谱和X针线粉末衍射的测定。     

Computation of suboptimal randomized strategies for steering the random motion of a point under partial observation

Consider the random motion in the plane of a pointM, whose velocityv=(v ₁,v ₂) is perturbed by an ²-valued Gaussian white noise. Only noisy nonlinear observations taken on the point location (state) are available toM. The velocityv is of the formv(y)= _u (u ₁,u ₂) _y (du), wherey denotes the value of the observed signal,U is the range of the velocity, and, for eachy, _y is a probability measure on (U). Using the available observations, the pointM wishes to steer itself into a given target set by choosing a randomized strategy ={ _y :y ²}. Sufficient conditions on weak optimal randomized strategies are derived. An algorithm for computing weak suboptimal randomized strategies is suggested, and the strategies are computed for a variety of cases.This work was partially supported by a grant from Control Data.