Characterization of bio-oil and bio-char produced by low-temperature microwave-assisted pyrolysis of olive pruning residue using various absorbers.

Olive pruning residue is largely formed during cultivation, and is usually disposed through open-air combustion directly in the field, but this habit is a possible source of pollution. The pyrolytic conversion of olive pruning residue has been run in a new and very appealing way using microwave as a heating source and different microwave absorbers in a multimode batch reactor. In this way, olive residue is converted into interesting bio-chemical products with a short pyrolysis time, ranging from 15 to 36 min, and with a peak temperature ranging from 450 K to 705 K according to the different microwave absorber. Thus, a very efficient and selective system was realized, which was able to address the process towards the formation of a large amount of bio-char (up to 61.2%) or a high formation of bio-oil (56.2%) and gas (41.7%) with a very low formation of bio-char (2.1%). However, when carbon and iron were used as microwave absorbers, it was possible to obtain an intermediate amount of bio-char (26-30%) and bio-oil (40 wt%). Bio-oils were collected as dark-brown liquids with low viscosity and density. A bio-oil with a low water concentration was obtained using carbon or iron as the microwave absorber. The bio-oils formed in all experiments contained a very large amount of acetic acid, even when NaOH was the microwave absorber. Furthermore, a large amount of aromatics were present in the bio-oil obtained using carbon as the microwave absorber.

A rare case of tibial hemimelia, surgical technique and clinical results.

We report a nine-year-old boy with a type IIIa tibial hemimelia, according to the new Paley classification. We describe the x-ray findings, the surgical treatment technique, and the prognostic course of the patient. Descriptions of such cases are very infrequent in the literature and type of treatment is still object of debate.

Protocol: A simple protocol for quantitative analysis of bio-oils through gas- chromatography/mass spectrometry.

A new and simple protocol for quantitative analysis of bio-oils using gas-chromatography/mass spectrometry is suggested. Compounds were identified via their mass spectra, and then unavailable response factors were calculated with respect to diphenyl as the internal standard using a modified method previously suggested for gas chromatography with flame ionization detection. This new protocol was applied to the characterization of bio-oils obtained from the pyrolysis of woods of different sources or using different pyrolysis procedures. This protocol allowed evaluation of the yields of products from poplar pyrolysis (among 50% and 99%), while a reduced amounts of products were identified from the pyrolysis of cellulose (between 46% and 58%). The main product was always acetic acid, but it was formed in very large yields from poplar while lower yields were obtained from cellulose.

Uncemented total hip arthroplasty in patients younger than 20 years.

BACKGROUND: Several diseases may lead to advanced hip disease and cause disabling symptoms in adolescents. In literature there is no consensus which is the optimal surgical treatment for young adults with end-stage osteoarthritis. The purpose of this study was to assess the clinical and radiological outcomes of uncemented total hip arthroplasty for the treatment of end-stage hip arthritis in patients younger than 20 years at a minimum follow-up of ten years. METHODS: We have retrospectively evaluated 24 patients who were 20 years or younger and underwent uncemented total hip arthroplasty. Minimum follow-up was 10 years. Clinical outcome was measured using the Harris Hip Score, Western Ontario McMaster, and the Short-Form 36. Hip calcification was evaluated using Brooker classification, while osteolysis was examined at the final follow-up according to the subdivision of Gruen. RESULTS: The mean preoperative Harris Hip Score was 36.94 points and improved to 92.3, and the mean preoperative WOMAC score improved from 84.72 to 28.45 The Mental Component score-SF-36 improved from a preoperative mean of 26.23 points to 58.96, while the Physical Component score-SF-36 improved from a preoperative mean of 26.38-49.95. All components were stable and osseo-integrated. Radiolucent lines were not present in any hips. We noted the presence of 4 calcifications. No patient needed implant revision. The only complication was an intraoperative femoral fracture. CONCLUSION: Total hip arthroplasty is a safe and reliable procedure for the treatment of end-stage arthritis in the young that provides good to excellent mid-term results.

Determination of GHB and its precursors (GBL and 1,4-BD) in dietary supplements through the synthesis of their isotopologues and analysis by GC-MS method.

Gamma-hydroxybutyric acid (GHB) and its "pro-drugs", gamma-butyrolactone (GBL) and 1,4 butanediol (1,4-BD), are drugs of abuse with depressant effects on the central nervous system. Many analytical methods have been proposed for the quantitative determination of these compounds mainly in biological matrices but only few have been addressed to dietary supplements and foods. Facile synthesis of the GBL and 1,4-BD isotopologues are available by "one pot" Ru-catalyzed homogeneous deuteration of dicarboxylic acids. In this work we propose a new method for determination of GHB, GBL and 1,4-BD in commercially available dietary supplements, based on isotope dilution mass spectrometry (ID-MS). The procedure involves a simple extraction of sample with acidic acetonitrile and direct analysis by GC-ID-MS method without any purification or derivatization. Indeed, the proposed method takes advantage of the complete conversion of GHB (free acid or its salts) to GBL, allowing the quantification of GHB and its pro-drugs. Five levels for each calibration curve have been prepared by diluting working solutions of the analytes to obtain concentrations ranging from 1 to 20mg/mL. The validation procedures have shown an accuracy between 88% and 99% and a precision between 7.3% and 2.9% of each analyte in the sample matrix. Positive ions chemical ionization (PICI) have been employed to preserve the information on molecular ions and to improve specificity and sensitivity of quantitative determination.

A convenient route to the synthesis of isotopomeric dihydro-2(3H)furanones.

A general synthetic procedure leading to isotopomeric dihydro-2(3H)furanones (gamma-butyrolactones) containing two, four, or six deuterium atoms has been developed. The labeled dihydro-2(3H)furanones were synthesized in quantitative yield from the saturated diacid C4 (succinic) or unsaturated diacids C4 (fumaric, maleic, or acetylendicarboxylic) in the presence of Ru4H4(CO)8(PBu3)4 using a deuterium pressure of 180 bar at 180 degrees C. This methodology was applied to the total synthesis of a hexadeuterated matairesinol lignan: The 3,4-bis[[3-methoxy-4-(phenylmethoxy)phenyl]methyl]dihydro-2(3H)furanone-[7,7',8,8',9',9'-D6] (benzyl-protected matairesinol-D6) was fully characterized.

Easy hydrolysis of white phosphorus coordinated to ruthenium.

The P4 molecule bound to ruthenium as an eta1-ligand in [CpRu(PPh3)2(eta1-P4)]Y (Y = PF6, CF3SO3) undergoes an easy reaction with water in exceedingly mild conditions to yield PH3, which remains coordinated to the [CpRu(PPh3)2] fragment, and oxygenated derivatives.