用两种方法合成长余辉发光玻璃的对比研究

在还原性气氛下高温固相反应法（一步法）合成了长余辉发光玻璃GA；用SrAl2O4:Eu,Dy荧光粉（SAED）与玻璃粉混合高温熔融（二步法）合成了长余辉发光玻璃GB和GC，通过XRD，发光光谱和磷光衰减曲线对样品进行了表征，荧光粉SAED和玻璃GA，GB，GC的发射峰值依次是525，493。462，516nm，发光强度和余辉时间都是SAED＞GC＞GB＞GA，玻璃的发射光谱峰随玻璃组成不同发生位移，两种发生合成的夜光玻璃发光性质存在明显的差异，同一合成方法下，玻璃基料决定着玻璃网络结构，同时也影响着夜光玻璃的发光性质。     

Determination of the Enantiomeric Purity of l-Carnitine and Acetyl-l-Carnitine by Chiral Liquid Chromatography

A chiral liquid chromatographic method for determination of the enantiomeric purity of both l-carnitine and acetyl-l-carnitine is described. Separation of the enantiomers of dl-carnitine and acetyl-dl-carnitine was achieved on a commercial chiral column (Chiralcel OD-R) after derivatization with (alpha-bromo)methyl phenyl ketone. Introduction of this lipophilic UV chromophoric group to the carnitine and acetylcarnitine molecules improved their retention, resolution, and UV detection. The mobile phase was 74:26 (v/v) 0.5 mol L^-1 sodium perchlorate–acetonitrile, pH 3.8, and the flow rate was 0.4 mL min^-1. Detection was performed at 235 nm. The method is selective and reliable for determination of the enantiomeric purity of bulk drug substances l-carnitine and acetyl-l-carnitine.     

Coordinating California’s efforts to promote waste to alcohol production

Alcohol fuels produced from biomass can improve air quality, enhance energy security, create employment opportunities, and reduce waste disposal problems. Opportunities in California exist to produce alcohols from waste streams from various sectors of the economy. Government agencies have promoted waste-to-alcohol activities, but efforts have been inconsistent and intermittent. Often these efforts have been hindered by contradictory but mandate-driven policies. A prudent approach to coordinate statewide efforts includes the development of an integrated statewide policy to examine barriers that impede private sector business efforts to produce alcohols from biomass. A multi-agency task force to promote research, development, commercialization, and marketing efforts for biomass-produced alcohols is desirable. The views and opinions contained in this document do not necessarily reflect those of the California Energy Commission, its staff, management, or the State of California.     

{(MesGa)3[GaP(H)Mes](PMes)4}, Ein phosphorsubstituiertes Ga?P-Heterocuban

{(MesGa)₃[GaP(H)Mes](PMes)₄}, a Phosphorus-substituted Ga? P-Heterocubane A mixture of MesGaCl₂/GaCl₃ (ratio 3:1) reacts with 5 equivalents of MesPLi₂ in THF at ?78°C to the title compound {(MesGa)₃[GaP(H)Mes](PMes)₄} ( 1 ) by use of the “dilution principle”. 1 can be obtained in 30% yield. Recrystallization of 1 from DME and toluene, respectively, gives 1 · 0.5 DME and 1 · toluene. 1 was characterized by NMR-, IR-, and MS-techniques. According to the X-ray structure determination of 1 · toluene, 1 has a heterocubane structure, one corner of which is substituted with an P(H)Mes group.     

Cellulose production based on hemicellulose hydrolysate from steam-pretreated willow

The production cost of cellulolytic enzymes is a major contributor to the high cost of ethanol production from lignocellulosics using enzymatic hydrolysis. The aim of the present study was to investigate the cellulolytic enzyme production ofTrichoderma reesei Rut C 30, which is known as a good cellulase secreting micro-organism, using willow as the carbon source. The willow, which is a fast-growing energy crop in Sweden, was impregnated with 1–4% SO₂ and steam-pretreated for 5 min at 206°C. The pretreated willow was washed and the wash water, which contains several soluble sugars from the hemicellulose, was supplemented with fibrous pretreated willow and used for enzyme production. In addition to sugars, the liquid contains degradation products such as acetic acid, furfural, and 5-hydroxy-methylfurfural, which are inhibitory for microorganisms. The results showed that 50% of the cellulose can be replaced with sugars from the wash water. The highest enzyme activity, 1.79 FPU/mL and yield, 133 FPU/g carbohydrate, was obtained at pH 6.0 using 20 g/L carbon source concentration. At lower pHs, a total lack of growth and enzyme production was observed, which probably could be explained by furfural inhibition.     

Synthesis of a biotinated amphiphile

The synthesis of a biotinated amphiphile assembled from d-(+)-biotin, ethylene diamine as spacer, galactaric acid and 1-dodecylamine was achieved in six steps. The key step was the synthesis of a bisacetonide protected galactaric ester, the structure of which was determined by X-ray analysis. Aminolysis, spacer attachment, coupling with biotin and deprotection led to the amphiphilic galactaramide.     

Total synthesis of d-(+)-biotin

A total synthesis of d-(+)-biotin is described starting from d-(+)-glucosamine using acyliminium chemistry.     

New alcohol resistant strains ofSaccharomyces cerevisiae species for potable alcohol production using molasse

Two alcohol resistant strains of Saccharomyces cerevisiae species were isolated from a Greek vineyard plantation. The strain AXAZ-1 gave a concentration of 17.6% v/v alcohol and AXAZ-2 16.5%, when musts from raisin and sultana grapes, respectively, were employed in alcoholic fermentations. They were found to be more alcohol tolerant and fermentative in the fermentation of molasse than the traditional baker's yeast. Specifically, using an initial [symbol: see text] Be density of 16 [symbol: see text] Be at the repeated batch fermentation process, in the first as well as fourth batch, the better AXAZ-1 gave final [symbol: see text] Be densities of 6.0 and 10.5 respectively, and the baker's yeast 11.6 and 14.5.     

A density functional study on a biomimetic non-heme iron catalyst: insights into alkane hydroxylation by a formally HO-FeV=O oxidant

The reactivity of [HO-(tpa)Fe(V)=O] (TPA=tris(2-pyridylmethyl)amine), derived from O-O bond heterolysis of its [H(2)O-(tpa)Fe(III)-OOH] precursor, was explored by means of hybrid density functional theory. The mechanism for alkane hydroxylation by the high-valent iron-oxo species invoked as an intermediate in Fe(tpa)/H(2)O(2) catalysis was investigated. Hydroxylation of methane and propane by HO-Fe(V)=O was studied by following the rebound mechanism associated with the heme center of cytochrome P450, and it is demonstrated that this species is capable of stereospecific alkane hydroxylation. The mechanism proposed for alkane hydroxylation by HO-Fe(V)=O accounts for the experimentally observed incorporation of solvent water into the products. An investigation of the possible hydroxylation of acetonitrile (i.e., the solvent used in the experiments) shows that the activation energy for hydrogen-atom abstraction by HO-Fe(V)=O is rather high and, in fact, rather similar to that of methane, despite the similarity of the H-CH(2)CN bond strength to that of the secondary C-H bond in propane. This result indicates that the kinetics of hydrogen-atom abstraction are strongly affected by the cyano group and rationalizes the lack of experimental evidence for solvent hydroxylation in competition with that of substrates such as cyclohexane.     

Gauge parameters for extrapolation of oscillator strengths ofE1 transitions along the boron isoelectronic sequence

The oscillator strengthsf forE1 transitions along an isoelectronic sequence can be written asf=aK ²+bK+c whereK is a gauge parameter representing the gauge condition of the electromagnetic field. The coefficientsa,b, andc are functions of length (f _l) and velocity (f _v) values of the oscillator strengths at the Hartree-Fock level. We have shown by making a perturbation expansion of oscillator strengthsf,f _l andf _v that the gauge parameterK is independent of the nuclear charge. This property has been exploited to extrapolatef values along the isoelectronic sequence of Boron for some representativeE1 transitions within then=2 complex. We obtain good agreement between the extrapolated results with the configuration interaction results.