Synergistic catalysis of the N-hydroxyphthalimide on flower-like bimetallic metal-organic frameworks for boosting oxidative desulfurization

Synergic catalytic effect between active sites and supports greatly determines the catalytic activity for the aerobic oxidative desulfurization of fuel oils.In this work,Ni-doped Co-based bimetallic metal-organic framework(CoNi-MOF)is fabricated to disperse N-hydroxyphthalimide(NHPI),in which the whole catalyst provides plentiful synergic catalytic effect to improve the performance of oxidative desulfurization(ODS).As a bimetallic MOF,the second metal Ni doping results in the flower-like morphology and the modification of electronic properties,which ensure the exposure of NHPI and strengthen the synergistic effect of the overall catalyst.Compared with the monometallic Co-MOF and naked NHPI,the NHPI@CoNi-MOF triggers the efficient activation of molecular oxygen and improves the ODS performance without an initiator.The sulfur removal of dibenzothiophene-based model oil reaches 96.4%over the NHPI@CoNi-MOF catalyst in 8 h of reaction.Furthermore,the catalytic product of this aerobic ODS reaction is sulfone,which is adsorbed on the catalyst surface due to the difference in polarity.This work provides new insight and strategy for the design of a strong synergic catalytic effect between NHPI and bimetallic supports toward high-activity aerobic ODS materials.

Gastrointestinal stromal tumors of the duodenum:Surgical management and survival results

AIM:To provide long-term survival results of operable duodenal gastrointestinal stromal tumors(DGISTs)in a tertiary center in China.METHODS:In this retrospective study,the pathological data of 28 patients with DGISTs who had been treated surgically at the Second Department of General Surgery,Sir Run Run Shaw Hospital(SRRSH)from June1998 to December 2006 were reviewed.All pathological slides were examined by a single pathologist to confirm the diagnosis.In patients whose diagnosis was not confirmed by immunohistochemistry at the time of resection,representative paraffin blocks were reassembled,and sections were studied using antibodies against CD117(c-kit),CD34,smooth muscle actin(SMA),vimentin,S-100,actin(HHF35),and desmin.Operative procedures were classified as wedge resection(WR,local resection with pure closure,without duodenal transection or anastomosis),segmental resection[SR,duodenal transection with Roux-Y or BillrothⅡgastrojejunostomy(G-J),end-to-end duodenoduodenostomy(D-D),end-to-end or end-to-side duodenojejunostomy(D-J)],and pancreaticoduodenectomy(PD,Whipple operation with pancreatojejunostomy).R0 resection was pursued in all cases,and at least R1 resection was achieved.Regional lymphadenectomy was not performed.Clinical manifestations,surgery,medical treatment and follow-up data were retrospectively analyzed.Related studies in the literature were reviewed.RESULTS:There were 12 males and 16 females patients,with a median age of 53 years(20-76 years).Their major complaints were"gastrointestinal bleeding"(57.2%)and"nonspecific discomfort"(32.1%).About14.3%,60.7%,17.9%,and 7.1%of the tumors originated in the first to fourth portion,respectively,with a median size of 5.8 cm(1.6-20 cm).Treatment was by WR in 5 cases(17.9%),SR in 13 cases(46.4%),and by PD in 10 cases(35.7%).The morbidity and mortality rates were 35.7%and 3.6%,respectively.The median post-operative stay was 14.5 d(5-47 d).During a follow-up of 61(23-164)mo,the 2-year and 5-year relapse-free survival was 83.3%and 50%,respectively.Eighty-four related articles were reviewed.CONCLUSION:Surgeons can choose to perform limited resection or PD for operable DGISTs if clear surgical margins are achieved.Comprehensive treatment is necessary.

Aerobic oxidative desulfurization via magnetic mesoporous silica-supported tungsten oxide catalysts

It is usually difficult to remove dibenzothiophenes from diesel fuels by oxidation with molecular oxygen as an oxidant.In the study,tungsten oxide was supported on magnetic mesoporous silica by calcination to form a magnetically separable catalyst for oxidative desulfurization of diesel fuel.By tuning different calcining temperatures,the catalyst calcined at 500℃showed a high catalytic activity with molecular oxygen as the oxidant.Under optimal reaction conditions,the sulfur removal of DBT reached 99.9%at 120℃after 8 h.Furthermore,the removals of 4-methyldibenzothiophene and 4,6-dimethyldibenzothiophene could also get up to 98.2%and 92.3%under the same conditions.The reaction mechanism was explored by selective quenching experiments and FT-IR spectra.

Enhanced adsorption performance for antibiotics by alcohol-solvent mediated boron nitride nanosheets

The development of high-efficient adsorbents for the treatment of antibiotics from contaminated water has been of great concern.This work introduced an alcohol-solvent mediated strategy to increase the specific surface area(SSA)and porosity of hexagonal boron nitride nanosheets(BNNSs)for improving tetracycline(TC)removal efficiency.The BNNSs synthesized with the mediation of n-propanol solvent(BN-P)exhibited the largest pore volume and relatively high SSA(increased by 34%and 64%,respectively,compared with that synthesized under the mediation of water)in its structure,which in turn facilitated the mass transfer of TC molecules onto BN-P framework.The remarkable adsorption performance of BN-P,with 20%increase in equilibrium adsorption capacity and Langmuir maximum adsorption capacity of 556 mg·g^(-1),was achieved for capturing TC within just 3 h,which is mainly through p-p interaction and electrostatic force.Pseudo-second kinetics equation can well illustrate the adsorption process,while Freundlich and Langmuir isotherm models fitted the equilibrium data well.Thermodynamics study demonstrated a spontaneous exothermal adsorption process.Furthermore,the strong environmental suitability and notable recycling performance of BN-P revealed its good application prospect in removing antibiotic TC from wastewater.