bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gold Nanoparticles Sliding on Recyclable Nanohoodoos—Engineered for Surface‐Enhanced Raman Spectroscopy
Authors: Wu Kaiyu , Li Tao , Schmidt Michael Stenbæk , Rindzevicius Tomas , Boisen Anja , Ndoni Sokol 
Published: November 2017

AbstractRobust, macroscopically uniform, and highly sensitive substrates for surface‐enhanced Raman spectroscopy (SERS) are fabricated using wafer‐scale block copolymer lithography. The substrate consists of gold nanoparticles that can slide and aggregate on dense and recyclable alumina/silicon nanohoodoos. Hot‐spot engineering is conducted to maximize the SERS performance of the substrate. The substrate demonstrates remarkably large surface‐averaged SERS enhancements, greater than 107 (>108 in hot spots), with unrivalled macroscopic signal uniformity as characterized by a coefficient of variation of only 6% across 4 cm. After SERS analyses, the nanohoodoos can be recycled by complete removal of gold via a one‐step, simple, and robust wet etching process without compromising performance. After eight times of recycling, the substrate still exhibits identical SERS performance in comparison to a new substrate. The macroscopic uniformity combined with recyclability at conserved high performance is expected to contribute significantly on the overall competitivity of the substrates. These findings show that the gold nanoparticles sliding on recyclable nanohoodoo substrate is a very strong candidate for obtaining cost‐effective, high‐quality, and reliable SERS spectra, facilitating a wide and simple use of SERS for both laboratorial and commercial applications.
Tubular TiO2 Nanostructures: Toward Safer Microsupercapacitors
Authors: Salari Maryam , Aboutalebi Seyed Hamed , Ekladious Iriny , Jalili Rouhollah , Konstantinov Konstantin , Liu Hua Kun , Grinstaff Mark W. 
Published: November 2017

AbstractSelf‐organized tubular nanostructures, synthesized through straightforward and efficient techniques, are anisotropic materials, catalyzing many research breakthroughs, and, are of interest as electrode materials for electrochemical microdevices. The fabrication and characterization of microsupercapacitors composed of self‐assembled titanium dioxide (TiO2) nanotubes, as a combined current collector and electrode, are described. Moreover, conventional toxic acidic or alkaline electrolytes are not required, and the device operates with phosphate buffered saline as the electrolyte. Higher volumetric capacitance (84 F cm−3) and energy density (1.15 mWh cm−3) values are obtained with the anodized TiO2 microsupercapacitor devices compared with the conventional ones that employ carbon‐based electrodes and organic electrolytes. Achieving high capacitance through the use of a safe neutral aqueous electrolyte, combined with the biocompatibility of TiO2 and Ti films, opens up new avenues for the utilization of this system and its design for energy delivery or harvesting in biological and medical applications.
Quaternary β2,2‐Amino Acids: Catalytic Asymmetric Synthesis and Incorporation into Peptides by Fmoc‐Based Solid‐Phase Peptide Synthesis
Authors: Yu Jin‐Sheng , Noda Hidetoshi , Shibasaki Masakatsu 
Published: November 2017

Abstractβ‐Amino acid incorporation has emerged as a promising approach to enhance the stability of parent peptides and to improve their biological activity. Owing to the lack of reliable access to β2,2‐amino acids in a setting suitable for peptide synthesis, most contemporary research efforts focus on the use of β3‐ and certain β2,3‐amino acids. Herein, we report the catalytic asymmetric synthesis of β2,2‐amino acids and their incorporation into peptides by Fmoc‐based solid‐phase peptide synthesis (Fmoc‐SPPS). A quaternary carbon center was constructed by the palladium‐catalyzed decarboxylative allylation of 4‐substituted isoxazolidin‐5‐ones. The N−O bond in the products not only acts as a traceless protecting group for β‐amino acids but also undergoes amide formation with α‐ketoacids derived from Fmoc‐protected α‐amino acids, thus providing expeditious access to α‐β2,2‐dipeptides ready for Fmoc‐SPPS.
Development of sericin/alginate particles by ionic gelation technique for the controlled release of diclofenac sodium
Authors: Vidart Jacyara Moreira Martins , Silva Thiago Lopes da , Rosa Paulo César Pires , Vieira Melissa Gurgel Adeodato , Silva Meuris Gurgel Carlos da 
Published: November 2017

ABSTRACTSericin and alginate particles, prepared by ionic gelation technique, demonstrated to be a promising matrix to controlled release of diclofenac sodium. Ten particle compositions of sericin, alginate, and diclofenac were evaluated. The drug incorporation was confirmed by scanning electron microscopy, Fourier Transform Infrared Spectroscopy, and X‐ray diffraction analysis. In vitro dissolution profile was performed to obtain the drug release profile in gastric and enteric medium. The drug release profile indicated that sericin delays the release and alginate contributes to the gastro‐resistance of formulations. The blend with composition of 2.5% of sericin, 2.8% of alginate with 2.0% w/v of diclofenac demonstrated to be feasible for drug delivery due the entrapment efficiency of 81.06% and release delay of 360 min, the highest time of all investigated compositions. The mathematical modeling showed that the drug release mechanism is associated to the process of swelling, matrix erosion, and a combination of diffusion and chain relaxation mechanisms. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45919.
COOHMWCNTs‐induced BiFeO3‐poly(vinylidene fluoride) (PVDF) composites with enhanced dielectric and ferroelectric properties
Authors: Moharana Srikanta , Mahaling Ram Naresh 
Published: November 2017

ABSTRACTIn this work, flexible three phase composite films were prepared with surface functionalized multi‐walled carbon nanotubes (f‐MWCNTs) and bismuth ferrite (BiFeO3;BFO) particles embedded into the poly(vinylidene fluoride) (PVDF) matrix via solution casting technique. The properties and the microstructure of prepared composites were investigated using an impedance analyzer and field emission scanning electron microscope. The micro‐structural study showed that the f‐MWCNTs and BFO particles were dispersed homogeneously within the PVDF matrix, nicely seated on the floor of the f‐MWCNTs separately. The dielectric measurement result shows that the resultant composites with excellent dielectric constant (≈96) and relatively lower dielectric loss (<0.23 at 100 Hz). Furthermore, the percolation theory is explored to explain the dielectric properties of the resultant composites. It says that the percolation threshold of fMWCNTs = 0.9 wt % and the enhancement of the dielectric constant of the composite was also discussed. In addition, the remnant polarization of the un‐poled PVDF‐BFO‐f‐MWCNTs composites (2Pr ∼1.34 µC/cm2 for 1.1 wt % of f‐MWCNTs) is also improved. These three phase composites provide a new insight to fabricate flexible and enhanced dielectric properties as a promising application in modern electrical and electronic devices. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46002.
Octadecyl‐silica—PVDF membrane of superior MD desalination performance
Authors: Mistry Rupal J. , Saxena Mayank , Ray Paramita , Singh Puyam S. 
Published: November 2017

ABSTRACTDespite its widespread industrial and residential uses for production of potable water, the reverse osmosis (RO) desalination process has some drawbacks by discharging harmful concentrated saline water as reject stream. A hydrophobic porous membrane can treat such environmentally unfriendly RO reject stream via Membrane Distillation (MD) process. Here, we describe preparation of superior polyvinylidenefluoride (PVDF) membrane modified with superhydrophobic silica nanoparticles for desalination application. Superhydrophobicity (contact angle of 151°) of silica nanoparticles of 7 nm sizes was achieved by reaction of the silica particles with octadecyltrichlorosilane in toluene to form SiOSi links with C18 alkyl chain. A homogeneous polymer dope mixture containing a desired amount of modified silica colloids suspended in toluene was used for the membrane preparation. The PVDF membrane with optimal silica content exhibited excellent flux with >99% salt rejection efficiency when used for MD at room temperature from the saline water feed of 3.5 wt % NaCl. The prepared hydrophobic PVDF membrane has the potential for MD application in treating the RO reject stream and other aqueous industrial effluents. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46043.
Analysis of euphotic depth in snow with SNICAR transfer scheme
Authors: Zhong Efang , Li Qian , Sun Shufen , Chen Shangfeng , Chen Wen 
Published: November 2017

AbstractSolar radiation in the visible spectrum can penetrate through snowpack to a considerable depth, which is named as the euphotic depth in snow. If the snow depth is no greater than the euphotic depth, the surface albedo is greatly affected by the underlying surface. This study defines the euphotic depth as the depth where the residual solar radiation in snow began to be less than 1.0 W m−2 and provides a convenient approach to estimate it. A two‐stream, multilayer radiation penetration model (SNow, ICe, and Aerosol Radiation) was applied to predict the vertical profiles of solar radiation based on regular measurements of snow pits and downward solar radiation at Col de Porte (CDP), France from 1993 to 2011. The euphotic depth in snow at CDP exhibits clear seasonal variations, with median values in winter months of 6.8, 8.8, and 10.5 cm, and those in spring remaining nearly on the same level (24.4 and 24.2 cm). The maximum euphotic depth at CDP reached as deep as 78 cm. Further analyses demonstrated that the euphotic depth in snow is related to not only the external initial solar irradiance but also the interior snow extinction coefficient. Stronger illumination and smaller snow extinction coefficients may correspond to greater euphotic depths in snowpack.
Growth rates of pulmonary metastases after liver transplantation for unresectable colorectal liver metastases
Authors: Grut H , Solberg S , Seierstad T , Revheim M E , Egge T S , Larsen S G , Line P D , Dueland S 
Published: November 2017

Abstract

Background
The previously reported SECA study demonstrated a dramatic 5-year survival improvement in patients with unresectable colorectal liver metastases (CLM) treated with liver transplantation (LT) compared with chemotherapy. The objective of this study was to assess whether immunosuppressive therapy accelerates the growth of pulmonary metastases in patients transplanted for unresectable CLM.

Methods
Chest CT scans from 11 patients in the SECA study resected for 18 pulmonary metastases were reviewed retrospectively. Tumour diameter, volume and CT characteristics were registered and tumour volume doubling time was calculated. Findings in the SECA group were compared with those of a control group consisting of 12 patients with non-transplanted rectal cancer resected for 26 pulmonary metastases. Disease-free survival (DFS) and overall survival (OS) after first pulmonary resection were determined.

Results
Median doubling time based on tumour diameter and volume in the SECA and control groups were 125 and 130 days (P = 0·658) and 110 and 129 days (P = 0·632) respectively. The metastases in both groups were distributed to all lung lobes and were mostly peripheral. Median DFS after LT in the SECA group and after primary pelvic surgery in the control group was 17 (range 6–42) and 18 (2–57) months respectively (P = 0·532). In the SECA group, estimated 5-year DFS and OS rates after first pulmonary resection were 39 and 51 per cent respectively.

Conclusion
Patients treated by LT for unresectable CLM have a good prognosis following resection of pulmonary metastases. Doubling time did not appear to be worse with the immunosuppression used after LT.
Quality of life in a randomized trial of early closure of temporary ileostomy after rectal resection for cancer (EASY trial)
Authors: Park J , Danielsen A K , Angenete E , Bock D , Marinez A C , Haglind E , Jansen J E , Skullman S , Wedin A , Rosenberg J 
Published: November 2017

Abstract

Background
A temporary ileostomy may reduce symptoms from anastomotic leakage after rectal cancer resection. Earlier results of the EASY trial showed that early closure of the temporary ileostomy was associated with significantly fewer postoperative complications. The aim of the present study was to compare health-related quality of life (HRQOL) following early versus late closure of a temporary ileostomy.

Methods
Early closure of a temporary ileostomy (at 8–13 days) was compared with late closure (at more than 12 weeks) in a multicentre RCT (EASY) that included patients who underwent rectal resection for cancer. Inclusion of participants was made after index surgery. Exclusion criteria were signs of anastomotic leakage, diabetes mellitus, steroid treatment, and signs of postoperative complications at clinical evaluation 1–4 days after rectal resection. HRQOL was evaluated at 3, 6 and 12 months after resection using the European Organisation for Research and Treatment of Cancer (EORTC) questionnaires QLQ-C30 and QLQ-CR29 and Short Form 36 (SF-36®).

Results
There were 112 patients available for analysis. Response rates of the questionnaires were 82–95 per cent, except for EORTC QLQ-C30 at 12 months, to which only 54–55 per cent of the patients responded owing to an error in questionnaire distribution. There were no clinically significant differences in any questionnaire scores between the groups at 3, 6 or 12 months.

Conclusion
Although the randomized study found that early closure of the temporary ileostomy was associated with significantly fewer complications, this clinical advantage had no effect on the patients' HRQOL. Registration number: NCT01287637 (https://www.clinicaltrials.gov).
Schedule dependent synergy of gemcitabine and doxorubicin: Improvement of in vitro efficacy and lack of in vitro‐in vivo correlation
Authors: Vogus Douglas R. , Pusuluri Anusha , Chen Renwei , Mitragotri Samir 
Published: November 2017

AbstractCombination chemotherapy is commonly used to treat late stage cancer; however, treatment is often limited by systemic toxicity. Optimizing drug ratio and schedule can improve drug combination activity and reduce dose to lower toxicity. Here, we identify gemcitabine (GEM) and doxorubicin (DOX) as a synergistic drug pair in vitro for the triple negative breast cancer cell line MDA‐MB‐231. Drug synergy and caspase activity were increased the most by exposing cells to GEM prior to DOX in vitro. While the combination was more effective than the single drugs at inhibiting MDA‐MB‐231 growth in vivo, the clear schedule dependence observed in vitro was not observed in vivo. Differences in drug exposure and cellular behavior in vivo compared to in vitro are likely responsible. This study emphasizes the importance in understanding how schedule impacts drug synergy and the need to develop more advanced strategies to translate synergy to the clinic.
Selective Production of Oxygenates from Carbon Dioxide Hydrogenation over a Mesoporous‐Silica‐Supported Copper‐Gallium Nanocomposite Catalyst
Authors: Hengne Amol M. , Bhatte Kushal D. , Ould‐Chikh Samy , Saih Youssef , Basset Jean Marie , Huang Kuo‐Wei 
Published: November 2017

AbstractThe hydrogenation of CO2 to oxygenates (methanol and dimethyl ether; DME) was investigated over bifunctional supported Cu catalysts promoted with Ga. The supported Cu‐Ga nanocomposite catalysts were characterized by using XRD, TEM with energy dispersive X‐ray spectroscopy, X‐ray photoelectron spectroscopy, and H2 temperature‐programmed reduction. In comparison with Cu‐SBA‐15‐based catalysts, the Ga‐promoted catalyst prepared by the urea deposition method (Cu‐Ga/SBA‐15‐UDP) was more active and selective for CO2 hydrogenation to oxygenates. The use of Ga as the promoter led to increased acidic sites, which was confirmed by using NH3 temperature‐programmed deposition and IR spectroscopy with pyridine and 2,6‐lutidine as probe molecules. The favorable effect of Ga on the CO2 conversion and selectivity to oxygenates may come from the strong interaction of Ga with silica, which is responsible for the enhanced metal surface area, the formation of the nanocomposite, and the metal dispersion. Notably, the incorporation of Ga into Cu/SiO2 led to a several‐fold higher rate for methanol formation (13.12 μmol gCu−1 s−1) with a reasonable rate for DME formation (2.15 μmol gCu−1 s−1) compared to Cu/SiO2 catalysts.
Dual Brønsted‐acid Organocatalysis: Cooperative Asymmetric Catalysis with Combined Phosphoric and Carboxylic Acids
Authors: Mitra Raja , Niemeyer Jochen 
Published: November 2017

AbstractHow can an assisting Brønsted‐acid be beneficial in asymmetric Brønsted‐acid catalysis? In this Minireview, we discuss selected examples of chiral organocatalysts that feature two acidic groups working cooperatively by virtue of intra‐ or intermolecular hydrogen‐bonding. In these systems, the assisting Brønsted‐acid can play different roles, ranging from simple hydrogen‐bond donation, to substrate‐binding or even as a nucleophilic reaction partner. By analysis of combined experimental, structural and theoretical data, we aim at developing a better understanding of the reaction mechanisms, which are largely influenced by the underlying intramolecular‐ and intermolecular catalyst‐substrate interactions. This may aid in the future development of more selective dual Brønsted‐acid organocatalysts for specific asymmetric transformations.
Advances in Nanocatalyst Design for Biofuel Production
Authors: Zuliani Alessio , Ivars Francisco , Luque Rafael 
Published: November 2017

AbstractThe exploitation of nanocatalysts, at the boundary between homogeneous and heterogeneous catalysis, offers new efficient ways to produce renewable biofuels in environmentally friendly conditions. Specifically, biodiesel and high density fuels have been chosen as major topics of research for the design of catalytic nanomaterials. As solid‐state catalysts, they are recyclable, and their nanometric particle size enables high activities that approach those of homogeneous catalysts. In addition, they offer novel and unique catalytic behaviors not accessible to solids above the nanometer range. Furthermore, the use of magnetically active materials has led to the development of nanocatalysts easily recoverable through the application of magnetic fields. In this Minireview, the latest achievements in the production of advanced biofuels using stable, highly active, cheap and reusable nanocatalysts are described.
Wiring Gold Nanoparticles and Redox Enzymes: A Self‐Sufficient Nanocatalyst for the Direct Oxidation of Carbohydrates with Molecular Oxygen
Authors: Ratautas Dalius , Ramonas Eimantas , Marcinkevičienė Liucija , Meškys Rolandas , Kulys Juozas 
Published: November 2017

AbstractThe development of artificial nanocatalysts, especially those incorporating the highly active biocatalysts (enzymes) present in nature, is a rapidly developing field in nanocatalysis and nanomaterials science. Dehydrogenases are exceptionally attractive, as they catalyze the oxidation of various cheap/common substrates to more expensive and desired products. However, their use in sustainable catalysis and/or their incorporation in advanced nanomaterials with catalytic functions are limited owing to one immense problem that can be formulated as a question: how can the electrons received from the oxidized substrate be removed? Here, a solution to this problem is demonstrated: we designed a unique nanomaterial composed of two redox enzymes (nonspecific glucose dehydrogenase and oxygen‐reducing laccase) and gold nanoparticles. Both enzymes were wired through the gold nanoparticles (10 nm) and direct electrochemical “communication” was achieved, allowing electron transfer from the redox center of glucose dehydrogenase to a copper center of laccase. As a result, self‐sufficient nanocatalysts were synthesized and shown to oxidize various carbohydrates directly with molecular oxygen.
Electrochemical Formation of Gold Nanoparticles on Polycrystalline Gold Electrodes during Prolonged Potential Cycling
Authors: Ahrens Paula , Zander Manfred , Hasse Ulrich , Wulff Harm , Jeyabharathi Chinnaya , Kruth Angela , Scholz Fritz 
Published: November 2017

AbstractThe voltammetric behavior of polycrystalline gold electrodes in 0.1 M sulfuric acid and the influence of prolonged repetitions of oxidation and reduction cycles at different scan rates on the surface morphology was studied. Slow (0.1 V s−1) as well as fast (1.0 V s−1) scan rates lead to an intense roughening of the electrode surface and the formation of a variety of different crystalline particles on it. These crystallites, their formation, and the influence of surface pretreatment were investigated with electrochemical methods, X‐ray diffraction measurements, and scanning electron microscopy. Additionally, an interpretation of the changing electrochemical signals of polycrystalline gold during prolonged potential cycling is given.
Eco‐friendly synthesis from industrial wastewater of Fe and Cu nanoparticles over NaX zeolite and activity in 4‐nitrophenol reduction
Authors: Elfiad Amal , Boffito Daria Camilla , Khemassia Sihem , Galli Federico , Chegrouche Salah , Meddour‐Boukhobza Laaldja 
Published: November 2017

AbstractWe deposited Fe and Cu over zeolite NaX (Fe/NaX and Cu/NaX) by adsorption from effluent industrial wastewater. We synthesized the zeolite NaX by the hydrothermal method. 5 g of NaX completely adsorbed 350 and 380 mg of Fe and Cu from the industrial wastewater, respectively, in 6 h. The distribution of Fe and Cu over the NaX was uniform and amounted at 14 and 18 mass%, respectively. Fe and Cu modify the morphology of the NaX zeolite: the particle size increased from 9 μm to 10 μm for the former and decreased to 3 μm for the latter. Fe/NaX and Cu/NaX are less crystalline than NaX. BET analysis showed that the specific surface area decreased by 30 % and 50 % compared to NaX for Fe/NaX and Cu/NaX, but the ratio between meso‐ and micropores increased by 7 and 13 times, respectively. Fe/NaX and Cu/NaX synthesized by adsorption from industrial wastewater reduced +99 % of 4‐p‐nitrophenol to 4‐aminophenol in less than 100 s, which is comparable to noble metal.
NMSBA produced from NMST under the catalysis of supported H3PW12O40 and Co/Mn/Br catalytic system
Authors: He Heng , Fang Zhou‐Wen , Zhang Chao , Long Xiang‐Li 
Published: November 2017

AbstractThe commercial production of 2‐nitro‐4‐methylsulphonylbenzoic acid (NMSBA) is oxidizing 2‐nitro‐4‐methylsulphonyltoluene (NMST) by nitric acid catalyzed with V2O5. A heterogeneous catalytic system composed of phosphotungstic acid supported on activated carbon, Co, Mn, and Br is used to catalyze the production of NMSBA from NMST by oxygen in this paper. The experiments show that the heterogeneous catalytic system composed of HPW@C, Co, Mn, and Br is capable of speeding up the oxidation of NMST to NMSBA by oxygen and acquiring a higher NMST oxidation rate and NMSBA yield than the homogeneous H3PW12O40/Co/Mn/Br catalytic system. The best HPW@C catalyst is obtained by supporting 0.0125 g/g H3PW12O40 on carbon followed by being calcined at 220 °C for 4 h under nitrogen atmosphere. The best heterogeneous catalytic system consists of 2.38 × 10−3 g/g HPW@C, 925 ppm Br, 236 ppm cobalt, and a Mn/Co molar ratio of 2.5. The usage of phosphotungstic acid in the heterogeneous system is diminished substantially.