Durable Hydrate-phobic Coating with In Situ Self-Replenishing Hydrocarbon Barrier Films for Low Clathrate Hydrate Adhesion.

Clathrate hydrate growth, deposition, and plug formation during oil and gas transportation causes blockage of pipelines. An effective strategy to solve this problem is to mitigate the hydrate formation and reduce its adhesion on pipe walls through a coating process. However, durability failure, corrosion, inability to self-heal, high cost, and strong hydrate adhesion remain unsolved issues.

Enhanced Surface Icephobicity on an Elastic Substrate.

Ice accumulation on exposed surfaces is unavoidable as time elapses and the temperature decreases sufficiently. To mitigate icing problems, various types of icephobic substrates have been rationally designed, including superhydrophobic substrates (SHSs), aqueous lubricating layers, organic lubricating layers, organogels, polyelectrolyte brush layers, electrolyte-based hydrogels, elastic substrates, and multicrack initiator-promoted surfaces. Among these surfaces, elastic substrates show excellent enhanced surface icephobicity during dynamic processes (i.

Designing small organic non-fullerene acceptor molecules with diflorobenzene or quinoline core and dithiophene donor moiety through density functional theory.

The non-fullerene acceptors A1-A5 with diflourobenzene or quinoline core (bridge) unit, donor cyclopenta[1,2-b:3,4-b']dithiophene unit and 2-(2-methylene-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile as acceptor unit with additional phenyl, fulvene or thieno[3,2-d]pyrimidinyl 5-oxide groups have been designed through DFT calculations. The optimization of molecular geometries were performed with density functional theory (DFT) at B3LYP 6-31G (d,p) level of theory. The frontier molecular orbital (FMO) energies, band gap energies and dipole moments (ground and excited state) have been calculated to probe the photovoltaic properties.

Comparative Analysis of Ethylene/Diene Copolymerization and Ethylene/Propylene/Diene Terpolymerization Using Ansa-Zirconocene Catalyst with Alkylaluminum/Borate Activator: The Effect of Conjugated and Nonconjugated Dienes on Catalytic Behavior and Polymer Microstructure.

The copolymerization of ethylene‒diene conjugates (butadiene (BD), isoprene (IP) and nonconjugates (5-ethylidene-2-norbornene (ENB), vinyl norbornene VNB, 4-vinylcyclohexene (VCH) and 1, 4-hexadiene (HD)), and terpolymerization of ethylene-propylene-diene conjugates (BD, IP) and nonconjugates (ENB, VNB, VCH and HD) using two traditional catalysts of C-symmetric metallocene-silylene-bridged rac-MeSi(2-Me-4-Ph-Ind)ZrCl (complex A) and ethylene-bridged rac-Et(Ind)ZrCl (complex B)-with a [PhC][B(CF)] borate/TIBA co-catalyst, were intensively studied. Compared to that in the copolymerization of ethylene diene, the catalytic activity was more significant in E/P/diene terpolymerization. We obtained a maximum yield of both metallocene catalysts with conjugated diene between 3.

Kinetic and Thermal Study of Ethylene and Propylene Homo Polymerization Catalyzed by -Zirconocene Activated with Alkylaluminum/Borate: Effects of Alkylaluminum on Polymerization Kinetics and Polymer Structure.

The kinetics of ethylene and propylene polymerization catalyzed by homogeneous metallocene were investigated using 2-thiophenecarbonyl chloride followed by quenched-flow methods. The studied metallocene catalysts are: -MeSi(2-Me-4-Ph-Ind)ZrCl (Mt-I), -Et(Ind)ZrCl (Mt-II) activated with ([MeNPh][B(CF)] (Borate-I), [PhC][B(CF)] (Borate-II), and were co-catalyzed with different molar ratios of alkylaluminum such as triethylaluminium (TEA) and triisobutylaluminium (TIBA). The change in molecular weight, molecular weight distribution, microstructure and thermal properties of the synthesized polymer are discussed in detail.

Biomass-Derived, Water-Induced Self-Recoverable Composite Aerogels with Robust Superwettability for Water Treatment.

Polluted water is a worldwide problem; therefore, effective separation of oil/water and removal of dyes, organic micropollutants, and heavy metals in wastewater are the need of the hour. Herein, hydrophilic β-cyclodextrin-grafted carboxymethyl cellulose, biodegradable polyvinyl alcohol, and chitosan were used as main raw materials to construct a multifunctional aerogel framework by simple sol-gel and directional freeze-drying methods. Featuring intrinsic superamphiphilic wettability in air, robust superoleophobic wettability underwater, and excellent shape-recovery characteristics, the biomass-derived aerogel presents durable oil/water separation even after 10 cycles.

Facile approach to design a stable, damage resistant, slippery, and omniphobic surface.

Creating a robust omniphobic surface that repels various liquids would have broad technological implications for areas ranging from biomedical devices and fuel transport to architecture. The present omniphobic surfaces still have the problems of complex fabrication methods, high cost, and being environmentally harmful. To address these challenges, here we report a novel process to design a non-fluorinated, long-term slippery omniphobic surface of candle soot nanoparticles with a silicone binder that cures at room temperature.

Durable and Scalable Candle Soot Icephobic Coating with Nucleation and Fracture Mechanism.

Ice formation and accretion affect residential and commercial activities. Icephobic coatings decrease the ice adhesion strength (τ) to less than 100 kPa. However, rare icephobic coatings remove the ice under the action of gravity or natural winds.

Highly Stable Amphiphilic Organogel with Exceptional Anti-icing Performance.

Various organogel materials with either a liquid or solid surface layer have recently been designed and prepared. In this work, amphiphilic organogels (AmOG) are innovatively developed from copolymer P(PDMS-r-PEG-r-GMA) and 2,2'-diaminodiphenyldisulfide via epoxy group addition reaction and then infiltrated with amphiphilic lubricants instead of traditional hydrophilic or hydrophobic lubricants. Because of synergistic effects of hydrophilic and hydrophobic segments of amphiphilic lubricants, the AmOG surfaces showed high stability and excellent anti-icing performance.

Icephobic Strategies and Materials with Superwettability: Design Principles and Mechanism.

Ice formation and accretion on surfaces is a serious economic issue in energy supply and transportation. Recent strategies for developing icephobic surfaces are intimately associated with superwettability. Commonly, the superwettability of icephobic materials depends on their surface roughness and chemical composition.

Evaluating the importance of different computed tomography scan-based factors in predicting the outcome of extracorporeal shock wave lithotripsy for renal stones.

Purpose: To evaluate the impact of various computed tomography scan-based parameters of renal stones on the outcome of extracorporeal shock wave lithotripsy (ESWL).

Materials And Methods: We conducted a retrospective study of patients who underwent ESWL for renal stones (sized 5-20 mm) from January 2013 to December 2016. We evaluated body mass index, location of the stone, skin-to-stone distance (SSD), stone attenuation value (SAV), stone diameter, Hounsfield density, stone area, and stone volume.

Justification For Re-Look Cystoscopy After Posterior Urethral Valve Fulguration.

Background: Posterior urethral valve (PUV) is life-threatening congenital anomaly of the urinary tract that results in vesicoureteric reflux, recurrent UTI, voiding dysfunction and renal insufficiency if not treat timely. Endoscopic ablation of posterior urethral valves using cold knife or laser is the current gold standard therapy. Many urologists go for repeat cystoscopy to see residual valve or stricture while others repeat VCUG to measure the posterior to anterior urethral ratio for residual obstruction.

EFFICACY OF ENDOSCOPIC TREATMENT FOR PRIMARY VESICOURETERIC REFLUX IN CHILDREN.

Background: Vesicoureteral reflux (VUR) is a common anomaly affecting 1-3% of all children and 30-50% of those with urinary tract infection (UTI). In the past febrile vesicoureteric reflux on chronic antibiotic prophylaxis were treated by open surgery. Now a day's endoscopic injection of a bulking material has replaced open surgical procedure in cases of primary VUR.

The Effect of Two Weeks Preoperative Finasteride Therapy in Reducing Prostate Vascularity.

Objective: To determine the effect of two weeks preoperative finasteride therapy in reducing prostate vascularity in terms of mean microvessel density (MVD) and expression of VEGF in prostate urothelium among patients of BPH by comparing with controls.

Study Design: Randomized controlled trial.

Place And Duration Of Study: Shifa International Hospital, Islamabad, from January 2013 to January 2014.

Female epispadias: spot diagnosis and simple reconstruction.

Isolated female epispadias without bladder exstrophy is a rare congenital anomaly. Patients present with total or partial urinary incontinence. The diagnosis can only be made on careful genitalia examination by separating the labia majora.

Neuroblastoma in horseshoe kidney.

Neuroblastoma is one of the commonest malignancy of childhood. Neuroblatoma in horseshoe kidney is an extremely rare condition. There is only one case of this tumour occurring in horseshoe kidney described in the literature.