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Pore engineered ZSM-5 zeolite in extrudate form was prepared and used as shape-selective catalyst for vapor phase ethylation of ethylbenzene to selectively form para -diethylbenzene. The physico-chemical properties of the catalyst were established by XRD, N 2 sorption, FTIR, FESEM, NH 3 -TPD and 31 P MAS NMR. Alkylation of ethylbenzene with ethanol was carried out in a continuous, down-flow, tubular reactor, at atmospheric pressure and H 2 as a carrier gas in vapor phase. Effect of silica to alumina ratio (SAR), crystal size, acidity of phosphate modified ZSM-5, stepwise phosphate modification and reaction conditions were studied in detail. ZSM-5 with SAR 187 was found to contain optimum acidity for phosphate modification to achieve good conversion and high selectivity for p -diethylbenzene. Under optimized reaction conditions, viz. temperature = 380 °C, ethylbenzene:ethanol mole ratio = 4:1, WHSV = 3 h −1 , H 2 /reactants = 2, 5PZSM-5 W catalyst gave 22.8% of ethylbenzene conversion with ∼98% selectivity for para -diethylbenzene. [ABSTRACT FROM AUTHOR]

The synthesis valuable para-dialkylbenzenes over shape selective zeolites is of immense industrial importance. The shape selectivity was achieved by regulating the pore mouth opening of ZSM-5 zeolites by employing chemical vapour deposition (CVD) of silica. Two probe molecules of different kinetic diameter were used to follow the extent of pore mouth regulation. The post synthesis modification resulted in obtaining para-substituted dialkylbenzenes of high purity by alkylation of monoalkylbenzenes with C1&z.sbnd;C3 alcohols.Similarly, para-substituted dialkylbenzene have been synthesised over pore size regulated zeolites by toluene disproportionation and paraffin aromatisation reactions. The above technique of enhancing para-selectivity has been successfully employed to develop an ecofriendly process for the manufacture of value added chemical para-diethylbenzene by ethylation of ethylbenzene. The paper highlights some of the unique advantages of pore size regulated zeolites for the synthesis of para-dialkylbenzenes over the conventional acid catalysed reactions. [Copyright &y& Elsevier]

Primary sarcoma of the ovary is extremely rare. There are inadequate data in the literature regarding ovarian sarcoma in the pediatric age group. We report a case of an 8-year-old girl presenting with large abdominal mass and cachexia. Raised alpha-fetoprotein levels suggested germ cell tumor. Tru-cut biopsy histopathological report suggested a spindle cell tumor. The IHC staining suggested non rhabdomyosarcoma. As tumour was large and ovarian pediatric non rhabdomyosarcoma was not reported in the literature, we started on rhabdomyosarcoma neoadjuant regimen. Good response was noted for neoadjuvant chemotherapy, which was followed by complete surgical excision of the tumor and radiotherapy. At present, the overall outcome of the disease is dismal. Increased available data and gaining more evidence may help in improvising the treatment option. [ABSTRACT FROM AUTHOR]

Alkylation of ethylbenzene (EB) with ethanol was carried out in a fixed bed, continuous, down-flow, tubular reactor at atmospheric pressure and hydrogen as a carrier gas in vapor phase. A detailed kinetic study was conducted over ZSM-5 zeolite extrudates pore-engineered by phosphate modification. The reaction was performed at EB: ethanol mole ratio of 4:1 and with varying contact time at temperatures of 613, 633 and 653 K. Due to the induced shape-selectivity in ZSM-5 by phosphate modification, para -diethylbenzene (PDEB) was formed as a major product and side products like benzene, meta -diethylbenzene (MDEB) and other isomers were formed in minor quantity. Langmuir–Hinselwood–Hougen–Watson (LHHW) method for dual site mechanism with an assumption of surface reaction controlling was applied to derive the rate equations. Activation energies for the ethylation of EB, dealkylation of EB and isomerization of PDEB were found to be 117.2, 186.0 and 298.6 kJ/mol respectively. Adsorption energetics showed that EB is weakly adsorbed, whereas ethanol is strongly adsorbed over the catalyst surface. Activation energy of PDEB formation was found to be lower than that of MDEB. Considering that the alkylation takes place mostly inside the zeolite channels, the results support restricted transition state selective mechanism for EB alkylation with ethanol over phosphate modified ZSM-5. Based on the proposed kinetic model, calculated values of EB conversion and PDEB formation were found to be in good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

Glycerol carbonate was synthesized by transesterification of glycerol with dimethyl carbonate using KF supported catalyst. KF was impregnated on various oxides and non-oxide supports like Al 2O 3, SiO 2, ZnO, ZrO 2, H-beta, and carbon to study the influence of the support on the catalytic performance. The preparation procedure of supported KF catalysts was modified to remove weakly adsorbed KF from the catalyst surface. The generation of basic sites by KF depends upon the extent of KF interaction with the support. KF/Al 2O 3 catalyst with optimized amount of 3.8 mmol KF, gave the highest activity with 95.8 % glycerol conversion and almost 100 % selectivity for glycerol carbonate. It was truly heterogeneous without any leaching of active sites and also showed good reusability. The catalyst exhibited better performance when compared to conventional solid base catalysts such as MgO, CaO and hydrotalcite. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Acid catalyzed carboxymethylation of alcohols is an emerging organic transformation that has grabbed the attention of scientific community in recent years. In the present study, sulfonated mesoporous polymer (MP-SO3H) is presented as a highly active solid acid catalyst to convert a wide range of alcohols into alkyl methyl carbonates. The remarkable catalytic activity of MP-SO3H is comparable to that of reported homogeneous acid catalysts. A good correlation was established between the catalytic activity and textural properties of the material. An exceptional catalytic activity of MP-SO3H was observed for DMC mediated carboxymethylation of bio-derived alcohols which is unmatchable to conventional resins and zeolites. This superior activity of MP-SO3H is ascribed to its intrinsic mesoporosity, high acid strength and uniform coverage of surface area by active sites. The catalyst is recyclable, resistant towards leaching and can be used in successive runs without losing the original activity. To the best of our knowledge, MP-SO3H is the first solid acid catalyst to exemplify highest activity for the synthesis of different alkyl methyl carbonates using DMC. The protocol developed herein opens up new avenues to transform wide range of bio-alcohols into useful organic carbonates in the future. [ABSTRACT FROM AUTHOR]

Background: Pelvi-ureteric junction obstruction (PUJO) is defined as anatomical or functional obstruction to the flow of urine from the pelvis to the upper ureter. This may be unilateral or bilateral. Most of the hydronephrosis cases are due to Pyelo-ureteral junction obstruction (PUJO) which can be diagnosed antenatally. The treatment protocol for antenatal diagnosed PUJO is standardized. Few children present later in life. Present study was done to evaluate clinical profile and outcome of infants and children (<12years) presenting with PUJO. Methods: A retrospective observational study conducted by the department of Paediatric Surgery, SDM hospital Dharwad. All children with age less than 12 years with PUJO from March 2017 to March 2020 were included in the study (n=51). Initial evaluation was done with Ultrasound KUB (Kidney, Ureter, Bladder). A diuretic renogram/EC (Ethylene cysteine) was done to confirm the diagnosis. The children were managed both conservatively and surgically (Pyeloplasty), depending on the presentation. The children were followed up post-surgery. Results: Fifty one patients were included in the study. Mean age of presentation was 31±30 months. Most common presentation was pain abdomen which was seen in 9 patients (17.6%). 6 patients (11.7%) presented with Lump and 2(4%) presented with fever. Left kidney was commonly involved (66%). Males predominate (80%). The mean antero-posterior pelvic dimension (APPD) of involved kidney was 30mm with range from 12.5mm to 68mm. 4 (7.8%) children presented with poorly functioning kidney with split renal function less than 10%. PUJO was associated with Pelvic calculi, VUR, Horseshoe kidney, Mal-rotated kidney. Out of the 51 patients, 9 (17.6%) were kept in conservative management 42 (82.3%) underwent Pyeloplasty. Among 42, 1 underwent redopyeloplasty and 1 underwent nephrectomy. In rest of the operated patients (Post-pyeloplasty) diuretic renogram showed improved drainage with improved function. Conclusions: PUJO is common cause of urinary obstruction in children. Earlier the diagnosis, better the outcome. Delay in diagnosis or presentation leads to increased chances of renal damage and loss. Hence it is important to diagnose PUJ obstruction at the earliest and receive prompt treatment. [ABSTRACT FROM AUTHOR]

A sulfonic acid-functionalized mesoporous polymer (MP-SO3H) catalyst was prepared via post-synthetic modification of mesoporous polydivinylbenzene by incorporating a sulfonic acid moiety using conc. H2SO4. The synthesized materials were characterized via several physicochemical techniques and their performance was evaluated for the room-temperature liquid-phase acetalization of glycerol with acetone. The MP-SO3H catalyst performed better than other conventional solid acid catalysts, with a 94% glycerol conversion and 98.5% selectivity for solketal. The high activity of the MP-SO3H catalyst was attributed to the facile diffusion of reactants and products in the mesoporous environment as well as to the high acidity. Glycerol conversion increased with increase in the total acidity of the catalyst. In addition, the acidity and surface density of (H+) ions were found to have a direct correlation with the catalyst performance. [ABSTRACT FROM AUTHOR]

Aim: Analyzeexperience with presentation, diagnosis and management of accidental ingested upper digestive tract foreign bodies in children. Materials: A prospective study of 60 pediatric patients from July 2009 to July 2014 with history of accidental ingested upper gastro intestinal foreign bodies. All patients were studied for age, gender, complaints, duration, site of impaction, type and complications. Radiological investigationswere taken according to the case. Direct laryngoscopy and Magill forceps or flexible esophagoscopy has been used for retrieval of foreign bodies. Results: Sixty caseswere analyzed age between 6months to 13 years. Male 42 and female 18. Age group 6months to 6 years constitutes 85%. Thirty six (60%) patients arrived to hospitalwithin 24 hours. Difficultly in swallowing (70%)was themost frequent symptom. Most foreign bodies were coin in the upper esophagus (70%). Preexisting esophageal disease was present in 20%. Out of 60 patients twenty four (40%) FB retrieved using Magill forceps and rest with Flexible esophagoscopy (60%). Foreign bodies were successfully removed without major complication in all cases. Mucosal erosions were seen in four patients after extraction. All patients except 4 were dischargedwithin 24 hours after the procedure. Conclusion: Children between 6 month to 6 years is the commonest age group affected. Magill forceps with the aid of a direct laryngoscope is a safe and effective method for proximal esophageal foreign body removal. But flexible esophagoscopy remains the safestmethod of upper digestive tract foreign body extraction. [ABSTRACT FROM AUTHOR]

A neonate with unilateral complete duplex system with congenital giant megaureter of the upper moiety presenting as abdominal lump is reported. A left upper moiety nephroureterectomy was performed. Such an anomaly with this presentation has not been reported in neonates. [ABSTRACT FROM AUTHOR]

We report a rare case of prune belly syndrome associated with congenital pouch colon, which was managed successfully. [ABSTRACT FROM AUTHOR]

A 4-year-old girl presented with non-bilious vomiting and loss of appetite and weight. At laparotomy, a non-communicating pyloroduodenal duplication cyst was present. Subtotal excision of the cyst and cauterization of the mucosal lining of the common wall was performed. The post-operative recovery was uneventful. [ABSTRACT FROM AUTHOR]