Syntheses and fluorescent properties of complexes of Eu（III） with HTTA, TPPO and benzoic acid

A series of Eu(III) complexes of α-thenoyltrifluoroacetone(HTTA) with trioctylphosphine oxide(TPPO) and benzoic acid(BA) or its two derivatives, p-toluic acid(PTA) and p-methoxybenzoic acid(POA) were synthesized and were characterized with elemental analysis, IR spectroscopy, scanning electronic microscopy and fluorescent spectra. The complexes were revealed to be Eu(BA)(TTA)₂TPPO₂, Eu(PTA)(TTA)₂TPPO₂ and Eu(POA)(TTA)₂TPPO₂. The excitation and absorption spectra of the complex Eu(POA)(TTA)₂TPPO₂ in MeOH solution were investigated in detail. The experimental result showed that relatively cheap materials with sharp red luminescence could be prepared, when benzoic acid or its two derivatives were added in Eu(III) complexes of α-thenoyltrifluoroacetone with trioctylphosphine oxide. The relative fluorescence intensity of the Eu(III) complexes decreased in the following order: Eu(POA)(TTA)₂TPPO₂> Eu(PTA)(TTA)₂TPPO₂>Eu(BA)(TTA)₂TPPO₂.     

Syntheses and fluorescent properties of complexes of Eu(Ⅲ) with HTTA,TPPO and benzoic acid

A series of Eu(Ⅲ) complexes of α-thenoyltrifluoroacetone(HTTA) with trioctylphosphine oxide(TPPO) and benzoic acid(BA) or its two derivatives, p-toluic acid(PTA) and p-methoxybenzoic acid(POA) were synthesized and were characterized with elemental analysis, IR spectroscopy, scanning electronic microscopy and fluorescent spectra. The complexes were revealed to be Eu(BA)(TTA)2TPPO2, Eu(PTA)(TTA)2TPPO2 and Eu(POA)(TTA)2TPPO2. The excitation and absorption spectra of the complex Eu(POA)(TTA)2TPPO2 in MeOH solution were investigated in detail. The experimental result showed that relatively cheap materials with sharp red luminescence could be pre-pared, when benzoic acid or its two derivatives were added in Eu(Ⅲ) complexes of α-thenoyltdfluoroacetone with trioctylphosphine oxide. The relative fluorescence intensity of the Eu(Ⅲ) complexes decreased in the following order: Eu(POA)(TTA)2TPPO2> Eu(PTA)(TTA)2TPPO2>Eu(BA)(TTA)2TPPO2.     

A ratiometric fluorescent nanoprobe based on ZIF-8@AuNCs-Tb for visual detection of 2,6-pyridinedicarboxylic acid

The rapid and sensitive detection of 2,6-pyridinedicarboxylic acid(DPA),one of the main biomarkers of Bacillus anthracis,is of great significance for the screening and diagnosing of anthrax.Herein,a ratiometric fluorescent nanoprobe based on zeolite imidazolate framework-8(ZIF-8)@AuNCs-Tb was constructed by embedding both gold nanoclusters(AuNCs) and terbium ions(Tb³⁺) into ZIF-8 for highresolution visual detection of DPA.Due to the aggregation induced emission enhancement(AIE) effect...     

List of Contents to Vol.8

Numberl,March 1990Reface···············‘·······一······························、、、、-、·、·,,···································,··…Xu Guangxian(l)Best Wishes to the Journal oftheChineseRareEarthsoeiety··············,···········,···················…MaFukang(2)Retardation ofPhotosensitized0xidationbyComPlexofHyPocrellinAandPraseodymiumlon .,二,.....…     

Selectivity adsorption of thiophene alkylated derivatives over modified Cu＋-13X zeolite

Solid adsorbents Cu+-13X and Cu+-13X loaded with La element were prepared by ion-exchange method. X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to characterize the structure of the prepared zeolite. Adsorption of thiophene with different groups over the two adsorbents was investigated by static adsorption equilibrium and kinetic test. Static equilibrium data were correlated based on the Langmuir model and the modified Langmuir model. Kinetic data were fitted very well by Crank diffusion model. The results revealed that the adsorption capacity of single component over the Cu+-13X loaded with La element increased about 10% as compared to the non-doped Cu+-13X. Fitting results of ηi and De illustrated that loading of the La element into zeolite could change the interaction force between binary components. The kinetic test showed that the competitive adsorption became moderate, and thus resulted in the improvement of the total desulfurization capacity.     

Improvement of Gold to Reducibility of La-Ce-Mn Catalyst under Lean Combustion

The effect of Au on the reducibility of La-Ce-Mn catalyst was studied in the synthetic exhaust gas mixture containing 10% oxygen. The characteristics of samples were analyzed by BET, SEM, XRD and activity evaluation. The resuits show that, in lean combustion, the performance of perovskite-type catalysts is evidently enhanced through adding Au, and specially a satisfying reducibility for NOx is demonstrated between 300～500℃. The catalytic activity of samples increases with the loading amount of Au, and the maximum conversion rate for NOx decomposition reaches up to 47% in 360～400℃. Moreover, the dispersivity and uniformity of the surface distribution of perovskite with Au have an important influence on the catalytic activity.     

Application of Fuzzy Logic Controller to Level Control of Twin-Roll Strip Casting

SymbolList　　D———Stripthickness ;　　E———Levelerror ;　　ΔE———Changeoflevelerror ;　　H———Moltensteellevel;　　L———Widthofcastingroll;　　Q———Volumeofmoltensteel;　　R———Radiusofcastingroll;　　S———Lateralareaofmoltensteelpool;　　u ,u1 ,u2 ———Outputofintelligentfuzzylogiccontrol ler,fuzzylogiccontrollerandPIDcon troller ;　　v———Castingspeed ;　　α———Proportionfactor ;　　τ———Time .　　Thetwin rollstripcastingprocessisanewstripproductionmethod …     

Synthesis and fluorescent properties of a novel europium（III） complex with terpyridine-capped poly（ethylene glycol）

Terpyridine-capped poly(ethylene glycol) (PEG) was synthesized as a novel polymeric ligand and rare earth complex was prepared from Eu(NO3)3 and the telechelic macromolecules. The structure of the complex was characterized by 1H NMR, FT-IR, UV-vis and fluores-cence spectroscopy. Strong fluorescent emission of the complex was observed at 593 and 616 nm upon the excitation of 300 nm. The fluo-rescent emission was quenched upon addition of trace amount of diethyl chlorophosphate (DCP). And the observed Ksv values for DCP were measured to be 0.568×103 and 0.89×103 L/mol for quenching at 593 and 616 nm, which indicated the detection limit for DCP was about 0.014 mmol/L. These results showed that the terpyridine-lanthanide complex could be an effective chemosensor with a potential application in the detection of organophosphates.     

New Methodological Approach to Investigation of Kinetics of REE Extraction in Nonstationary Conditions

The influence of periodical oscillations of the temperature on extraction and stripping processes in the extraction systems was studied. Two extraction systems were investigated： （1） 6 mol · L^-1 NaNO3-Nd（NO3）3-Pr（NO3）3-TBP kerosene and （2） [Nd（NO3）3 · 3TBP] -[ Pr（NO3）3 · 3TBP] -kerosene - 0.1 mol · L^-1 HNO3. Mathematical modeling of the nonstationary membrane extraction has been enhanced by including the dependence of the extraction rate constants on temperature. The values of activation energy for direct and reverse extraction and stripping reactions of Pr and Nd were calculated from experimental temporal dependencies of metal concentration and temperature by solving the reverse kinetics problem using the proposed mathematical model, A series of experiments with periodical oscillations of the temperature on the extraction system for the separation of rare earth elements （REE） using bulk liquid membrane between two extractors were performed. The mathematical model adequately describes the experimental data. The optimization of the extraction process for separation of REE by liquid membrane, under the influence of periodical oscillation of the temperature, was made based on the extraction rate constants and activation energies. The optimal conditions of separation by liquid membrane were found： frequency and amplitude of thermal oscillations, liquid membrane flow rate, and optimal ratio between organic and aqueous phase in extractors.     

Coexistence Theory of Slag Structure and Its Application to Calculation of Oxidizing Capability of Slag Melts

1　ＣｏｅｘｉｓｔｅｎｃｅＴｈｅｏｒｙｏｆＳｌａｇＳｔｒｕｃｔｕｒｅＴｈｅｓｔａｎｄｐｏｉｎｔｏｆｔｈｅｃｏｅｘｉｓｔｅｎｃｅｔｈｅｏｒｙｏｆｓｌａｇｓｔｒｕｃｔｕｒｅｉｓｔｈａｔｓｌａｇｍｅｌｔｓｃｏｎｓｉｓｔｏｆｍｏｌｅｃｕｌｅｓａｎｄｉｏｎｓ.Ｔｈｉｓｓｔａｎｄｐｏｉｎｔｃａｎｂｅｃｏｎｆｉｒｍｅｄｂｙｔｈｅｆｏｌ ｌｏｗｉｎｇｆａｃｔｓ :(1)Ｆａｃｔｓｉｎｃｒｙｓｔａｌｃｈｅｍｉｓｔｒｙ :Ｔｈｅｏｘｉｄｅｓｉｎｓｏｌｉｄｓｔａｔｅ ,ｓｕｃｈａｓＣａＯ ,ＭｇＯ ,ＭｎＯ ,ＦｅＯ ,ｅｔｃ .,ａｒｅ…     

Hydroxylation Reaction of Phenol to Catechol on Lanthanide-Zirconia Catalyst

ＨｙｄｒｏｘｙｌａｔｉｏｎＲｅａｃｔｉｏｎｏｆＰｈｅｎｏｌｔｏＣａｔｅｃｈｏｌｏｎＬａｎｔｈａｎｉｄｅ－ＺｉｒｃｏｎｉａＣａｔａｌｙｓｔＤｅｎｇＧｕｏｃａｉ（邓国才）；ＬｉｕＸｉｎｙｉｎｇ（刘歆颖）；ＸｕＬｉ（徐莉）ＬｉＭｅｎｇｑｉｎｇ（李梦青）；Ｍ...     

Fear of contagion: a response to stress?

Alterations of neutrophil functions by tobacco products may play a central role in the pathogenesis of periodontal diseases and several smoking-related systemic diseases. In the present study, we examined the in vitro effects of cigarette smoke on neutrophils at times and concentrations that may be encountered during smoke exposure. We measured the level of smoke exposure in the in vitro system by measuring the levels of nicotine and comparing these to levels in the oral cavity in smokers before and after smoking. We examined both the unstimulated and stimulated release of 2 oxidative burst products: superoxide (O-2) and hydrogen peroxide (H2O2). Salivary washings were collected from 7 smokers (> 1 pack/day) before smoking a cigarette. Immediately after they smoked a cigarette, a second set of washings was collected. In vitro exposure to smoke involved incubating aliquots of neutrophils in phosphate-buffered saline for 1 to 5 minutes. Nicotine and cotinine levels were quantitated using gas chromatography, with detection by electron impact mass spectrometry. Peripheral neutrophils were isolated from medically healthy non-smoking volunteers via a double-density gradient technique and incubated in vitro with whole cigarette smoke for 0 to 5 minutes. Phorbol myristate acetate (PMA; 10(-7) M) was used to stimulate half of the cell aliquots. Superoxide generation was assessed through the superoxide dismutase (SOD) inhibitable reduction of ferricytochrome c. H2O2 production was assessed through the H2O2-dependent breakdown of dichlorofluorescin diacetate to its fluorophore and measured by flow cytometry. There was a marked elevation in salivary nicotine concentration from before smoking (mean: 80.8 ng) to after smoking (mean 1,685 ng/mL). In the in vitro smoke box system, there was a time-related elevation in nicotine from 1 to 5 minutes (50-->136 ng/mL). In PMA-stimulated cells exposed to smoke, there was a time-related inhibition of both superoxide and H2O2 production. However, in unstimulated cells exposed to smoke, there was a time-related increase in the release of superoxide and H2O2. A novel finding in unstimulated cells exposed to smoke was that there appeared to be 2 distinct populations of cells--one of "high" H2O2 producers and one of "low" H2O2 producers. The proportion of high H2O2 producers increased relative to smoke exposure. The relative production of H2O2 in the unstimulated high producers was comparable to PMA-stimulated cells at 5 minutes. This release of superoxide and H2O2 in unstimulated cells exposed to smoke may alter the pathogenic processes both in periodontal diseases and other systemic diseases.     

Simulation of Case Depth of Cementation Steels According to Fick＇s Laws

 The carburizing process is the enrichment of the depth of low carbon steels with carbon. It leads to samples with a combination of high surface hardness and high core toughness and to an impact strength that is required for many engineering parts. The material studied is a low carbon steel. The carbon content is little in this type of steel (wC=0.2%). The calculation of case depth is very important for cementation steels that are hardened in the carburizing process. The effective case depth is defined as the perpendicular distance from the surface to a place at which the hardness is HV 550. Nowadays, a great number of studies have been carried out on the simulation of effective case depth, but no studies have been conducted to determine the numerical relation between the total case depth on one hand and the carburizing time and the effective case depth on the other hand. The steel specimens were subjected to graphite powder. Then, they were heat treated at 925 ℃ for about 3, 5, 8 and 12 h, respectively. Then, these parts were quenched in oil. To determine the effective case depth, the microhardness test was performed on the cross-section of specimens. Plotting the case depth vs carburizing time, the required conditions for obtaining the specified case depth were determined. Also, the comparison between the case depths in numerical solution and the actual position in pack carburizing was performed.     

Growth Rate of China''''s Metal Trade Expected to Slowdown

According to preliminary statistics,China'simport & export of non-ferrous metals areexpected to experience a slowdown in 2004,especially in the growth rate of export,andeven a zero growth rate will show up in the firstquarter.The factors that will affect the importand export of non-ferrous metals in 2004 havebeen analyzed as follows:as the adjustedexport tax refund rates became effectivestarting from January 1~(st),2004,the end of 2003had seen large amount of non-ferrous export by     

First Phase of Nanchuan Alumina Project of Chongqing to Go into Operation in July

The first phase of Nanchuan aluminum project,a key project of Chongqing municipalityundertaken by Nanchuan Minerals Group ofChongqing with an investment of 2.5 billion     

Journal of Rare Earths List of Contents to Vol.10 (1992)

Num加rl,March 1992Studies on the ComPlexes of Rare Earth wirh organie Ligands Containing SulPhur Atoms 、PreParation and ProPerties ofHeavy RareEarthPiPeridinoearbodithioateComPlexes ··············“······”·······“······……Tang Ning,Gan xin一Min,Zhang Wei一Guang,Xuc Ll一Lln.丁an Mm一Yu(l)Synthesis and ProPerties ofZ:I8SeriesHeteroPolytungstoPhosphateCompoundswithLanthanon ·……‘··”····……’·,.··“··“”············…     

Journal of Rare Earths List of Contents to Vol.9 (1991)

N帅加rl,March 1991Rare Earth ComPlexes ofAminoPolyearboxyljeAeidII.synthesisandstruetureofLanthanumComp1exofoipieolin一e^eid ··················,·…Jin Tian一Zhu,Liu Jun一Kang,Zhang Hui一Zhen,Huang Chun一Hui,XuGuang一Xian et al.(l)DeterminationofComPos1tionsandStabilityConstantsofHolmiumandYttriumComPlexeswithTribromoarsenazo by Line盯Regression Method··································一··················……W…     

Toxicity of Lanthanum to Pathogenic Fungi and Its Morphological Characteristics

Rare earth (RE) ,a kind of natural mineral hasbeen used as a beneficial element to crops for quite alongti me . Withthe solution of a series of keytechnolo-gies such as extraction,separation of radioactive ingre-dients ,sanitary toxicology,and environmental safety,China became the first countryto apply commercial REproducts asfertilizer or growthsti mulatorin agriculture ,which produced considerable economic and social ben-efits[1 ,2].RE has been found to have some controllingeffects on many…     

Are individuals' reputations related to their history of behavior?

[Correction Notice: An erratum for this article was reported in Vol 98(1) of Journal of Personality and Social Psychology (see record 2009-24670-012). Coefficient alpha reliabilities for the social connectedness variable were reported as .97 and .78 in Studies 2 and 3, respectively. Instead, they should have been reported as intraclass correlations (ICC) of .87 and .74, respectively. In the original reliability analyses, the authors included self-ratings of social connectedness and thus omitted participants from the analysis who did not provide a self-rating. Similarly, the authors included self-ratings when assessing the reliability of social connectedness in an unreported classroom sample (n=36) that was collected at the same time as the data reported in Study 2. In that unreported sample, they originally obtained a coefficient that was far below satisfactory levels, leading them to exclude that data set. However, after taking out the self-ratings in that unreported sample, the ICC was .82. The erratum summarizes the correlations reported in Study 2 for the unreported and included data sets combined.] Functional theories of reputation imply that individuals' reputations are tied to their history of behavior. However, indirect evidence suggests that the relation between reputation and behavior might be tenuous at best. In 3 studies, the authors tracked the development of reputations among individuals who engaged in multiple negotiation tasks across several weeks. The authors found that on average, individuals' reputations were only mildly related to their history of behavior. However, the link between reputation and behavior was stronger for some individuals than others--specifically, for individuals who were more well-known and received more social attention in the community. In contrast, for less well-known individuals, their behavior had little impact on their reputation. The findings have implications for psychologists' understanding of reputations, person perceptions in larger groups, and the costs and benefits of social visibility. (PsycINFO Database Record (c) 2010 APA, all rights reserved)