Peculiarities of isotopic temperatures obtained from p + A collisions at 1 GeV

Nuclear temperatures were extracted from fragment yields obtained in inclusive measurements of p+A collisions at 1 GeV. All thermometers based on double-isotopic yield-ratios provide temperatures T ≃ 4 MeV nearly independent on the target mass.     

Solid phase extraction and determination of metal ions in aqueous samples using Quercetin modified Amberlite XAD-16 chelating polymer as metal extractant

A new chelating polymer has been developed using Amberlite XAD-16 anchored with Quercetin. The modified polymer was characterised by Fourier Transform Infra Red (FTIR) spectroscopy, thermogravimetric analysis, surface area analysis and elemental analysis. The Quercetin anchored polymer showed superior binding affinity for Cr(III), Mn(II), Fe(III), Co(II), Ni(II) and Cu(II) with greater than 95% adsorption under optimum conditions. The optimum pH conditions for the quantitative sorption of metal ions were studied. The developed method showed superior extraction qualities with high metal loading capacities of 387, 313, 195, 473, 210 and 320 µmol g^?1 for Cu(II), Co(II), Cr(III), Fe(III), Mn(II) and Ni(II), respectively. The rate of metal ion uptake i.e. kinetics studies performed under optimum levels, showed t _1/2 for Co(II), Cu(II), Cr(III), Fe(III), Mn(II) and Ni(II) is 20, 15, 25, 10, 30 and 15 min, respectively. Desorption of metal ions was effective with 10 mL of 2 M HCl prior to analysis using flame atomic absorption spectrophotometer. The chelating polymer was highly ion selective in nature even in the presence of interferent ions, with a high preconcentrating ability for the metal ions of interest. The developed chelating polymer was tested on its utility with synthetic and real samples like river, tap water samples and also with multivitamin tablets. It showed relative standard deviation (R.S.D.) values of/less than 3.0% reflecting on the accuracy and reproducibility of data using the newly developed chelating polymer.     

AN EFFICIENT SYNTHESIS OF POLYMETHYLENE-BIS-AROYL THIOUREA DERIVATIVES UNDER THE CONDITION OF PHASE-TRANSFER CATALYSIS

Reaction of polymethylene diamine with aroyl chloride and ammonium thiocyanate under the condition of solid–liquid phase-transfer catalysis using polyethylene glycol-400 (PEG-400) as the catalyst yielded polymethylene-bis-aroyl thiourea derivatives 3a–q in good-to-excellent yield. The products have been characterized by analytical and spectral (IR and H¹ NMR) data.     

A Facile and Efficient Solid Supported,One‐Pot Synthesis of Functionalized Piperidine Derivatives Catalyzed by Amberlite IRA400‐Cl Resin/I2/KI via Multicomponent Reaction

A facile and efficient one‐pot, solid supported synthesis of functionalized piperidine derivatives catalyzed by Amberlite IRA400‐Cl resin/I₂/KI via a multicomponent reaction of various aldehydes, aromatic amines, and 1,3‐dicarbonyl compounds has been achieved. The reaction has been carried out in a one‐pot reaction and Amberlite resin as a solid supported catalyst at room temperature. Shorter reaction time, easy workup, yield, and mild reaction condition make the novel synthetic strategy both practical and attractive.     

Expedient Method for Oxidation of Alcohol by Hydrogen Peroxide in the Presence of Amberlite IRA 400 Resin (Basic) as Phase‐Transfer Catalyst

Amberlite IRA 400 (strongly basic), a classical polymer imparts phase‐transfer catalysis in the oxidation of primary and secondary alcohols by hydrogen peroxide to give excellent yields of the corresponding carbonyl compounds or carboxylic acids in acetonitrile solvent at reflux temperature in 4–6 h. The catalytic system is inert to other susceptible oxidation sites such as carbon–carbon double bonds     

CeCl3 · 7H2O‐KI‐Catalyzed,Environmentally Friendly Synthesis of N,N′‐Disubstituted Ureas in Water Under Microwave Irradiation

N,N′‐Disubstituted ureas were efficiently synthesized by reactions of urea with a variety of amines in water under microwave irradiation using CeCl₃ · 7H₂O‐KI as catalyst. This protocol has advantages of not using toxic phosgene and hazardous organic solvents, high reaction rate, high yield, and a simple workup procedure.     

Determination of rare earth elements in seawater by inductively coupled plasma mass spectrometry with off-line column preconcentration using 2,6-diacetylpyridine functionalized Amberlite XAD-4

An off-line column preconcentration technique using a micro-column of 2,6 diacetylpyridine functionalized Amberlite XAD-4 with inductively coupled plasma mass spectrometry (ICP-MS) as a means of detection has been developed. The aim of the method was to determine rare earth elements (REEs) (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) in seawater. Sample solutions (2–10 mL) were passed through the column which was then washed with ultra-pure water to remove residual matrix. The adsorbed cations on the resin were eluted by using 2 mL of 0.1 mol L⁻¹ HNO₃ containing 10 ng mL⁻¹ indium as an internal standard. The eluent was analyzed for the metal concentrations using ICP-MS. Sample pH as well as the sample and eluent flow rates were optimized. The sorption capacity of resin was determined by the batch process, by equilibrating 0.05 g of the resin with solutions of 50 mL of 25 mg L⁻¹ of individual metal ions for 4 h at pH 6.0 at 26 °C. The sorption capacities for the resin were found to range between 47.3 μmol g⁻¹ (for Lu) and 136.7 μmol g⁻¹ (for Gd). Limits of detection (3σ), without any preconcentration, ranged from 2 ng L⁻¹ to 10.3 ng L⁻¹ (for Tm and Lu respectively). The proposed method was applied to the determination of REEs in seawater and tap water samples.     

Amberlite XAD-2000树脂固相萃取富集-火焰原子吸收法测定水中痕量铅

用Amberlite XAD-2000树脂键合8-羟基喹啉固相萃取富集水中痕量铅,然后用火焰原子吸收法测定。实验了pH,样品处理速度,洗脱剂的类型、用量、浓度、处理速度等因素对铅回收率的影响。在最优条件下,树脂对铅的最大吸附量7.2 mg Pb/g树脂,回收率92%;且该方法抗干扰能力强,可用于环境水样检测和干扰离子存在下（如海水中）痕量铅的检测。