Solvent extraction separation of In/III/-Tl/III/ and Hg/II/-Cd/II/-Co/II/ with sulphoxides

Solvent extraction studies have been made on some metals: In/III/-Tl/III/ and Hg/II/-Cd/II/-Co/II/, from ammonium thiocyanate solutions by dialkyl sulphoxides. Separation of these metals from one another can be achieved by suitable choice of the extracted conditions. The nature of the extractable metal species has been elucidated.     

Synthesis of chlorobis/β-diketonato/oxotechnetium/V/ and tris/β-diketonato/technetium/III/ complexes

Chlorobis/-diketonato/ oxotechnetium/V/ complexes [TcOCl/-dik/₂, -diketone=acetylacetone, benzoylacetone and dibenzoylmethane] were newly synthesized using macroamount of⁹⁹Tc. These complexes were further separated into geometrical isomers. Furthermore, an improvement of the yields for the syntheses of tris/-dike-tonato/technetium/III/ complexes [Tc/-dik/₃, -diketone=acetylacetone, benzoylacetone and 2-thenoyltrifluoroacetone] was examined using Tc/III/-thiourea complexes as a starting material.     

Separation of Tl/III/ from Tl/I/

A method for the separation of Tl/III/from Tl/I/ is reported employing 1-/2-pyridylazo/-2-naphthol /PAN/ and Rhodamine-B as extracting agents.     

在发光二极管背光源上极具应用前景的Beta-sialon (Si6-zAlzOzN8-z):Eu2+窄带绿色荧光粉

基于氮化镓的白光发光二极管(LED)是目前一项崭新的背光源技术,广泛应用于宽色域、高光效的液晶显示屏。 在此项技术中,作为关键材料的荧光粉决定着背光单元的色域范围、发光效率和可靠性,因而要求它应具合适的发射波长和窄带发射。 β-sialon:Eu²⁺(sialon:silicon aluminum oxynitride(赛龙))就是一款非常适合背光应用的绿色荧光粉,这得益于其位于525~545 nm发射峰和只有55 nm狭窄的峰宽。 此文回顾和综述了β-sialon:Eu²⁺的合成方法、光谱特性、电子结构、晶体结构、可靠性和它的具体应用。 计算模拟和实验测试结果表明,Eu²⁺位于沿c轴方向的大孔道之中,并与6个最紧邻的(O,N)原子等距离配位。 因而,Eu²⁺的狭窄发射峰源自于Eu²⁺局域结构的高度对称性。 β-sialon:Eu²⁺的发射波长和带宽都能通过组成裁剪,即z值,进行调控;低z值组成能够实现更短波长发射和更窄带宽。 与传统的基于钇铝石榴石(YAG)荧光粉的背光源相比,β-sialon:Eu²⁺再搭配红色荧光粉制备的背光源具有更宽的色域,色域范围可提高15%以上。 其优异的发光性能和高可靠性使得β-sialon:Eu²⁺成为应用于先进显示屏的极其重要的绿色发光材料。     

Base hydrolysis of halobis/8-quinolinolato/ oxotechnetium/V/ complexes

Reaction mechanism of base hydrolysis of halobis/8-quinolinolato/oxotechnetium (V) /TcOX (ox)₂ X=Cl and Br/ was investigated by means of solvent extraction and spectrophotometric methods. Furthermore, distribution coefficients of tris/acetylacetonato/technetium/III/, dichlorobis/8-quinolinolato/technetium/IV/ and TcOX/ox/₂ between chloroform and aqueous solutions were determined. In an alkaline solution, TcOX/ox/₂ decomposed to pertechnetate as a final product. On the basis of the established base hydrolysis, the respective rate constants were determined.     

CALCULATED RATES AND EQUILIBRIA OF THERMAL INTERCONVERSION OF TRIPLET (3g-) AND SINGLET (1Δg and g+) MOLECULAR OXYGEN

Abstract— From spectroscopic data and rate constants in the literature, equilibrium constants and rates of thermal formation of singlet oxygen (¹Δ_g and ¹Σ_g⁺) were calculated for a number of conditions. For the gas phase we estimate K _eq(¹Δ_g³Σ_g^-) = 1.67 exp(-94.31 KJ/RT) and K _eq(¹Σ_g⁺/³Σ_g^-) = 0.33 exp(-157.0 KJ/RT). The calculated rate constants for the ³Σ_g⁺→¹Δ_g transition of O₂ at 25°C varied from 2.5 × 10^-11 s^-1 in water to 4.8 × 10^-16 s^-1 in air, assuming equal solvent interactions with the ground and excited states. Physical quenchers for singlet oxygen are expected to be catalysts for its thermal formation. Equations are presented which allow one to estimate whether such catalysis by quenchers will result in a pro-oxidant effect.     

THERMODYNAMIC FUNCTIONS FOR SINGLET MOLECULAR OXYGEN, O2(1△g) and O2 (1σ8+)

Abstract— A correction is offered to the approximate values previously given by Mendenhall (1978) for the enthalpy of formation and entropy of O₂(a₁Δ_g) and O₂(b₁₊) between 298 and 1500 K. Accurate values have been calculated for the functions together with the equilibrium constants for the formation of these species from O₂(X₃σ_g-).     

Separation of Th/IV/ and U/VI/ by extraction chromatography

Application of extraction chromatographic technique to the analytical separation of Th/IV/ and U/VI/ has been investigated. The stationary phase was a macroporous resin Amberlite XE-270 impregnated with undiluted trin-n-butylphosphate /TBP/ and the mobile phase was either 5.OM HNO₃ or 6M HCl. Separation of traces of Th/IV/ from large quantities of U/VI/ was achieved on a laboratory column by elution of the absorbed Th/IV/ with 6M HCl.     

DEPENDENCE OF Pfr/Ptot-RATIOS ON LIGHT QUALITY and LIGHT QUANTITY

Abstract— Not only the spectral distribution of the light source determines the relative proportion of phytochrome in the P_fr(P_r) form, the P_fr/P_tot-ratio also depends strongly on the fluence rate of the irradiation. This dependence has been observed in the cotyledons of etiolated mustard seedlings for blue light of fluence rates below 20 Wm_-2. It has also been observed for white light and seems to be a characteristic of the phytochrome system resulting from the involvement of phytochrome thermal reactions as well as P_r P_fr photoconversions. The fluence rate dependence of P_fr/P_tot-ratios can be used to analyze the characteristic transformations of the phytochrome system. Phototransformations together with a fast thermal transformation (τ_½⋍ 3min) are consistent with the results obtained for blue and white light.     

XPS analyses on Ta/Au/NiFe/NiO/Ta films

In this study, Ta/NiFe/NiO/Ta films were prepared by magnetron sputtering. The Au layer inserted at the interface of Ta and NiFe significantly influences the exchange bias field (H_ex) of the Ta/NiFe/NiO/Ta films. The Hex of the film with 0.9 nm Au layer increased by 28% compared with that of the film without a Au layer. The results show that the Au layer inserted at the interface of Ta and NiFe segregated at the surface of the NiFe/NiO in Ta/Au/NiFe/NiO/Ta films. The Au layer insulated the direct contact and suppressed the interface reaction between the NiFe and NiO layers, thus increasing the Hex. Copyright © 2015 John Wiley & Sons, Ltd.     

荧光粉Ba5-3x/2B4O11∶xEu3+的制备及发光性能

采用高温固相烧结法成功制备了Ba_5-3x/2B₄O₁₁∶xEu³⁺(x=0.02~0.22)荧光粉,利用XRD和SEM等对荧光粉进行了结构和形貌表征。 在激发波长为393 nm的条件下,发射峰(596、621、657和706 nm)与Eu³⁺的⁵D₀-⁷F_J(J=1,2,3,4)电子跃迁相对应,其中621 nm最强发射峰由Eu³⁺离子⁵D₀→⁷F₂电偶极跃迁造成。 文章还研究了Eu³⁺掺杂浓度对Ba_5-3x/2B₄O₁₁∶xEu³⁺发光性能的影响,结果表明,荧光粉的发光强度随着Eu³⁺掺杂量的增加呈现先增大后减小的趋势,Eu³⁺最佳掺杂量为0.16。     

Calorimetric study of the BrO3?/Ce4+/cyclohexanone and BrO3?/Ce4+/cyclopentanone oscillating systems

The heat output (Q) during the induction period of a Belousov-Zhabotinskii oscillating reaction usually evolves at a constant rate /6/; we observe in the BrO ₃ ^– /Ce⁴⁺/Cyclohexanone system a sudden change in the slope of the function Q=f(t), which corresponds to the beginning of the quasistationary phase /3/.

---

(Q) - ; BrO ₃ ^– /Ce⁺⁴/ Q=f(t), .

     

Exploiting the complementary nature of LC/MALDI/MS/MS and LC/ESI/MS/MS for increased proteome coverage

The goal of this work was to evaluate the improvement in proteome coverage of complex protein mixtures gained by analyzing samples using both LC/ESI/MS/MS and LC/MALDI/MS/MS. Parallel analyses of a single sample were accomplished by interfacing a Probot fractionation system with a nanoscale LC system. The Probot was configured to perform a post-column split such that a fraction (20%) of the column effluent was sent for on-line LC/ESI/MS/MS data acquisition, and the majority of the sample (80%) was mixed with a matrix solution and deposited onto the MALDI target plate. The split-flow approach takes advantage of the concentration sensitive nature of ESI and provides sufficient quantity of sample for MALDI/MS/MS. Hybrid quadrupole time-of-flight mass spectrometers were used to acquire LC/ESI/MS/MS data and LC/MALDI/MS/MS data from a tryptic digest of a preparation of mammalian mitochondrial ribosomes. The mass spectrometers were configured to operate in a data dependent acquisition mode in which precursor ions observed in MS survey scans are automatically selected for interrogation by MS/MS. This type of acquisition scheme maximizes the number of peptide fragmentation spectra obtained and is commonly referred to as shotgun analysis. While a significant degree of overlap (63%) was observed between the proteins identified in the LC/ESI/MS/MS and LC/MALDI/MS/MS data sets, both unique peptides and unique proteins were observed by each method. These results demonstrate that improved proteome coverage can be obtained using a combination of these ionization techniques.     

Y2O3包覆LiCo1/3Ni1/3Mn1/3O2的电化学性能

通过在硝酸钇水溶液浸渍并焙烧的简单工艺, 在LiCo1/3Ni1/3Mn1/3O2材料表面包覆了一层Y2O3. 采用X射线衍射(XRD), 扫描电子显微镜(SEM), 透射电子显微镜(TEM), 循环伏安(CV)和恒流充放电对包覆和未包覆的LiCo1/3Ni1/3Mn1/3O2进行了测试分析. 结果表明, Y2O3包覆并没有改变LiCo1/3Ni1/3Mn1/3O2的晶体结构, 只存在于LiCo1/3Ni1/3Mn1/3O2的表面; 与未包覆的材料相比, Y2O3包覆后的材料在高电位下具有更好的容量保持率和放电容量. CV测试表明, 包覆层的存在有效抑制了材料层状结构的转变及电极与电解液的负反应.     

Studies on licand displacement of thiourea in technetium/III/-coordination compounds by chlorine and 1,2 bis/diphenylphosphino/-ethane /dppe/

Ligand displacement reaction between Tc/III/-thiourea complexes and the model ligand 1,2 bis/diphenylphosphino/ ethane /dppe/ were investigated. The results appear unfavourable to the purpose of synthesizing Tc/III/ dppe complexes.     

Electrochemical performance of a nano SnO2-modified LiNi1/3Co1/3Mn1/3O2 cathode material

The nano SnO₂-modified LiNi_1/3Co_1/3Mn_1/3O₂ was successfully prepared by a carrier transfer method. The pristine and modified samples were characterized with various techniques such as XRD, SEM, XPS and EDS. The results showed that the SnO₂ particles did not enter the crystal structure of LiNi1/3Co1/ 3Mn1/3O₂, many nano SnO₂ particles were uniformly covered on the surface of LiNi_1/3Co_1/3Mn_1/3O₂ and the modified thin layer could inhibit the dissolution of transition metal oxides. The electrochemical tests indicated that the existence of nano SnO₂ could improve the discharge capacity and rate capability owing to the decreased interfacial polarization. The cycling stability was remarkably improved at room temperature and 55 ℃. The XRD patterns of the fresh NCM electrode and after 50 cycles proved that the structural change of NCM was not so effective on the capacity fade.     

TiO2包覆对LiCo1/3Ni1/3Mn1/3O2材料的表面改性

为了提高材料LiCo1/3Ni1/3Mn1/3O2的循环性能, 采用浸渍-水解法对其进行TiO2包覆. 用X射线衍射(XRD)、电化学交流阻抗谱(EIS)、电感耦合等离子体发射光谱(ICP-OES)和恒流充放电测试研究包覆材料的结构和电化学性能. TiO2仅在材料表面形成包覆层, 并未改变材料的结构. TiO2包覆能提高材料LiCo1/3Ni1/3Mn1/3O2的倍率性能和循环性能, TiO2包覆后的材料在5.0C(1.0C=160 mA·g-1)下的放电容量达到0.2C下的66.0%, 而包覆前的材料在5.0C下的放电容量仅为其0.2C下的31.5%. 包覆后的材料在2.0C下循环12周后的容量没有衰减, 而未包覆的材料容量保持率仅为94.4%. EIS测试表明包覆材料性能的提高是由于循环过程中材料的界面稳定性得到了提高. 循环后材料的XRD和ICP-OES测试表明, 包覆层能提高材料LiCo1/3Ni1/3Mn1/3O2的结构稳定性.     

Recoil implantation reaction in geometrical isomers of tris/benzoylacetonato/chromium/III/

Hot atom chemical reaction by⁵⁰Cr/n, /⁵¹Cr and⁵²Cr/, n/⁵¹Cr reactions, and recoil implantation reaction by⁵¹V/p, n/⁵¹Cr reaction were investigated using geometrical isomers /mer and fac/ of tris/benzoylacetonato/ chromium/III/ /Cr/ba/₃/. The production of counter isomer was observed for both mer- and fac-targets, although the yield of labelled parent isomer was larger. The observed mer/fac yield ratio suggests that the main formation mechanism of⁵¹Cr/ba/₃ is the reaction of ba^– and Cr/ba/ ₂ ⁺ which has the same geometrical configuration of target complex, and the substitution reaction of central metal atom by recoil⁵¹Cr. Furthermore, implantation gave rise to a much higher yield of labelled Cr/ba/₃ compared to the case of in situ nuclear recoils.     

Homochiral cyclopentane-based C1-symmetric P,P ligands C5H8(PPh2)(PR2) from C2-symmetric C5H8(PCl2)2

Treatment of 1,2-trans-C₅H₈(PCl₂)₂ with 1,2-C₂H₄(NHPr-i)₂ gave the C₂-symmetric perhydro-1,6,2,5-diazaphosphocine C₅H₈{P(Cl)N(Pr-i)CH₂}₂-cyclo, which produced dissymmetric C₅H₈(PPh₂){P[N(Pr-i)CH₂]₂-cyclo} on further reaction with PhMgBr. Cleavage of the P---N bonds with gaseous HCl afforded C₅H₈(PPh₂)(PCl₂), which was converted to C₅H₈(PPh₂){P(OPh)₂}₂ by reaction with phenol. All chiral P,P derivatives were obtained as racemates as well as resolved (1R,2R)- and (1S,2S)-enantiomers.