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Thiophene sulfide is difficult to be removed by hydrodesulfurization. In this study, ZnCl2-waste paper fiber activated carbon was used as adsorbent to remove thiophene sulfide from simulated oil by hydrothermal modification. Under the optimum condition of ammonia modification, the adsorption capacity of modified adsorbent to BT is 14.8 mg S/g, 2.98 times that of unmodified. BET, FTIR and Boehm analysis showed that the mesopore volume of ammonia modified adsorbent increased by 96.62% and the mesopore ratio increased from 12.58% to 43.40%, which was conducive to improving the adsorption rate. After modification, the basic groups on the surface of the adsorbent increased by 44.3 times, and –NH3+, –OH and –NH2 enhanced the electron attraction and hydrogen bonding force between the adsorbent and BT molecule. Adsorption isotherms, adsorption kinetics and adsorption thermodynamics show that the adsorption process is spontaneous, entropic and exothermic. The pseudo-second-order kinetic rate constant increases with the increase of adsorption temperature, indicating that the increase of temperature is beneficial to accelerate the adsorption rate. The adsorption desulfurization process follows the mechanism of single and multilayer adsorption mixing. The results of this study can help to reveal more clearly that biobased activated carbon can be modified to adsorb thiophene sulfide. Ammonia modified adsorbents enhance the adsorption capacity for benzothiophene [ABSTRACT FROM AUTHOR]

Nickel nanoparticles was supported on sawdust carbon via a hydrothermal method followed by calcination and used as a catalyst for heavy crude oil upgrading experiment. The performance of catalyst on catalytic pyrolysis of heavy crude oil was studied by laboratory experiments. The experimental results showed that under the reaction conditions of 350 °C, 30 min and 0.1 wt% catalyst, the viscosity reduction ratio of heavy crude oil was 74.50%, the viscosity can be reduced from 16,000 mPa·s (50 °C) to 4080 mPa·s, and the net efficiency of catalyst was 14.37%. Analysis results suggested that the viscosity reduction of heavy crude oil was caused by the destruction of structure of resin in the process of the catalytic pyrolysis reaction. [ABSTRACT FROM AUTHOR]

Objectives: This study aims to: (i) evaluate the outcome of patients with Harrington class III lesions who were treated according to Harrington classification; (ii) propose a modified surgical classification for Harrington class III lesions; and (iii) assess the efficiency of the proposed modified classification. Methods: This study composes two phases. During phase 1 (2006 to 2011), the clinical data of 16 patients with Harrington class III lesions who were treated by intralesional excision followed by reconstruction of antegrade/retrograde Steinmann pins/screws with cemented total hip arthroplasty (Harrington/modified Harrington procedure) were retrospectively reviewed and further analyzed synthetically to design a modified surgical classification system. In phase 2 (2013 to 2019), 62 patients with Harrington class III lesions were classified and surgically treated according to our modified classification. Functional outcome was assessed using the Musculoskeletal Tumor Society (MSTS) 93 scoring system. The outcome of local control was described using 2‐year recurrence‐free survival (RFS). Owing to the limited sample size, we considered P < 0.1 as significant. Results: In phase 1, the mean surgical time was 273.1 (180 to 390) min and the mean intraoperative hemorrhage was 2425.0 (400.0 to 8000.0) mL, respectively. The mean follow‐up time was 18.5 (2 to 54) months. Recurrence was found in 4 patients and the 2‐year RFS rate was 62.4% (95% confidence interval [CI] 31.6% to 93.2%). The mean postoperative MSTS93 score was 56.5% (20% to 90%). Based on the periacetabular bone destruction, we categorized the lesions into two subgroups: with the bone destruction distal to or around the inferior border of the sacroiliac joint (IIIa) and the bone destruction extended proximal to inferior border of the sacroiliac joint (IIIb). Six patients with IIIb lesions had significant prolonged surgical time (313.3 vs 249.0 min, P = 0.022), massive intraoperative hemorrhage (3533.3 vs 1760.0 mL, P = 0.093), poor functional outcome (46.7% vs 62.3%, P = 0.093), and unfavorable local control (31.3% vs 80.0%, P = 0.037) compared to the 10 patients with IIIa lesions. We then modified the surgical strategy for two subgroup of class III lesions: Harrington/modified Harrington procedure for IIIa lesions and en bloc resection followed by modular hemipelvic endoprosthesis replacement for IIIb lesions. Using the proposed modified surgical classification, 62 patients in the phase 2 study demonstrated improved surgical time (245.3 min, P = 0.086), intraoperative hemorrhage (1466.0 mL, P = 0.092), postoperative MSTS 93 scores (65.3%, P = 0.067), and 2‐year RFS rate (91.3%, P = 0.002) during a mean follow‐up time of 19.9 (1 to 60) months compared to those in the phase 1 study. Conclusion: The Harrington surgical classification is insufficient for class III lesions. We proposed modification of the classification for Harrington class III lesions by adding two subgroups and corresponding surgical strategies according to the involvement of bone destruction. Our proposed modified classification showed significant improvement in functional outcome and local control, along with acceptable surgical complexity in surgical management for Harrington class III lesions. [ABSTRACT FROM AUTHOR]

The coexistence of distinct insulating and metallic phases within the same manganite sample, i.e., phase separation scenario, provides an excellent platform for tailoring the complex electronic and magnetic properties of strongly correlated materials. Here, based on an electric-double-layer transistor configuration, we demonstrate the dynamic control of two entirely different phases—canted G-type antiferromagnetic metal and C-type antiferromagnetic charge/orbital ordered insulator phase—in electron-doped system Ca1−xCexMnO3 (x = 0.05). The reversible metal-to-insulator transition, enhanced colossal magnetoresistance (∼ 27 000% for Vg = 3.0 V), and giant memory effect have been observed, which can be attributed to an electronic phase separation scenario manipulated by a tiny doping-level-variation of less than 0.02 electrons per formula unit. In addition, the controllable multi-resistance states by the combined application of magnetic and electrostatic fields may serve as an indicator to probe the dynamic multiphase competition of strongly correlated oxides. These results offer crucial information to understand the physical nature of phase separation phenomena in manganite systems. [ABSTRACT FROM AUTHOR]

A transition metal oxide catalyst of copper oxide nanoparticles was synthesized by a conventional non-hydrothermal method. It was studied as a catalyst in thermocatalytic upgrading and viscosity reduction of heavy oil in the laboratory. The experimental results showed that the viscosity of heavy oil may be reduced by 85.75% with 0.2 wt% catalyst at 350 °C for 40 min. With determinations of analyzation, it was found that under the thermocatalytic action of copper oxide nanoparticles, the presence of hydrogen-donor in the reaction could further improve the chemical constitution of resin and asphaltene in heavy oil. [ABSTRACT FROM AUTHOR]

Cr3+ contained sulfuric acid aqueous solution and β-PbO2/Ti anode were prepared for electrochemical oxidation-distillation desulfurization of straight-run gasoline. Strong oxidant (Cr2O72−) was formed and reacted with organic sulfides. The oxidized sulfides were removed by distillation. Under optimal operating conditions, the desulfurization rate of gasoline reached to 99.16%.β-PbO2/Ti electrode were characterized by XRD and SEM. Model oil was analyzed by FTIR and GC-MS and the possible desulfurization mechanism was proposed. The recycling experiments of the electrolyte showed its excellent stability, but the concentration of H+ in electrolyte should be monitored, since the water will be consumed in electrolysis process, and the over-high H+ concentration is not good for the formation of Cr2O72−. [ABSTRACT FROM AUTHOR]

Ferroelectric thin films have been systematically investigated via scanning probe microscopy in recent years. Research indicates that the surface potential is the combined result of injected and polarization charges. The relationships between surface potentials and the two types of charges are usually investigated via scanning Kelvin probe microscopy (SKPM). Typically, SKPM investigations indicate that the surface charge distribution is dominated by injected charges trapped during poling using a conductive AFM tip rather than by polarization charges. The presence of injected charges leads to controversy concerning the origins of resistive switching behavior. In this study, relaxation of injected charges was observed during an optimized thermal treatment. This caused polarization charges to dominate over injected charges. Different electroresistance switching characterizations were observed via conductive atomic force microscopy (C-AFM) of injected and polarization charge-dominated films. Our research extends the methods of distinguishing whether electroresistance switching behavior is driven by charge trapping/detrapping or ferroelectric polarization. This provides an effective approach to classifying the origins of electroresistance switching in ferroelectric thin films by combining piezoelectric force microscopy, SKPM, and C-AFM. [ABSTRACT FROM AUTHOR]

Objective: Limb salvage in pediatric patients remains a challenge. We describe a staged strategy. The procedure includes: (i) tumor removal and non‐hinged static endoprosthesis reconstruction; (ii) leg length discrepancy (LLD) correction by shoe lift or distraction osteogenesis; and (iii) maturity reconstruction by regular endoprosthesis. The aim of the study was to investigate the results of non‐hinged static megaprosthesis reconstruction and staged LLD correction in the treatment of malignant tumors in the distal femur in children. Methods: Non‐hinged megaprostheses were implanted in 12 pediatric patients with osteosarcoma in the distal femur. The prosthesis consists of a femoral component with constrained condylar knee (CCK) design, and a tibial component with a small‐diameter press‐fit stem and derotation fins. A posterior stabilizing polyethylene component is fixed on the tibial component. The cases were prospectively followed up with focus on the growth rate of adjacent uninvolved bone in the salvaged limb, joint stability, knee stability, function outcome, length discrepancy, and surgery‐related complications. Results: There were five girls and seven boys included in the study, with an average age at the time of primary surgery of 10.0 years (range, 8–12 years). All the tumors were located in the distal femur. The average follow up was 76.3 months (range, 24–139 months). The Ligament Augmentation and Reconstruction System (LARS) ligament was used in two patients to enhance the soft tissue reattachment and reconstruct medial collateral ligament (MCL). Ten patients were alive at the final follow‐up and two had died of lung metastases. Expected LLD was 6.7 cm (range, 3.0–13.2 cm) at initial surgery. At the final follow‐up, nine patients reached skeletal maturity and the actual LLD at the femur was 5.3 cm (range, 3.0–10.1 cm), excluding 1 cm correction at initial surgery by endoprosthesis. The proximal tibia physis showed an average of 86.7% (range, 56.5%–100%) growth of the contralateral side. The mean reduction in tibial length was 1.2 cm (range, 0.5–4.7 cm). Six patients received distraction osteogenesis at a mean length of 5.4 cm (range, 3.0–9.1 cm). Range of knee movement was between 85° and 125°, with an average of 102.5°. The Musculoskeletal Tumor Society 93 score of patients alive was 80.6 (range, 60–90). Conclusion: Non‐hinged static megaprosthesis followed by LLD correction with shoe lift or staged distraction osteogenesis appears to be an alternative option to treat children with malignant bone tumors around the knee. [ABSTRACT FROM AUTHOR]

As an emerging phenomenon in oxide heterostructures, the ferroelectric control of electronic transport is attracting considerable research attention. However, the effect of ferroelectric polarization on resistive switching (RS) remains controversial. In this study, to determine the effects of ferroelectric polarization on memory characteristics, ferroelectric and non-ferroelectric BaTiO3 (BTO) films were fabricated using different oxygen partial pressures (Po2) during film growth. A correlated electron oxide, SmNiO3 (SNO), was selected as the bottom electrode. Based on piezoelectric force microscopy, ferroelectricity was verified in the BTO films prepared at Po2 ≥ 3 Pa, whereas the films fabricated at lower Po2 did not exhibit ferroelectricity. Remarkable RS with an ON/OFF ratio of 104% was clearly observed in heterostructures containing ferroelectric BTO, while RS was negligible in structures with non-ferroelectric BTO. The strong ferroelectricity dependence of RS behavior on the BTO/SNO heterostructures was attributed to the ferroelectric control of device transport between bulk-limited current in the low-resistance state and interface-limited conductance in the high-resistance state, which results from the modulation of the potential barrier at the BTO/SNO interface. The findings provide strong evidence for the dominant effect of ferroelectric polarization of BTO on the transport properties of BTO/SNO heterostructures. [ABSTRACT FROM AUTHOR]

In this paper, choosing the mixed solution of MnSO4solution and H2SO4as electrolyte, with the progressing of electrolysis reaction, Mn3+was generated as intermediate product, combining with water to produce the oxidation agent MnOOH, which was easy to oxidize the sulfur compounds to generate sulfoxide or sulfone. At the optimal electrochemical oxidation desulfurization conditions, the sulfur content of kerosene decreased from 180 µg/g to 8.87 µg/g and the desulfurization efficiency reached to 95.07%. And the cycle of electrolyte and mechanism of electrochemical oxidation desulfurization has been discussed. [ABSTRACT FROM AUTHOR]

A novel high acid site density carbon-based solid acid catalyst was prepared and first applied in the FCC gasoline alkylation desulfurization. The catalyst was synthesized by a facile approach and characterized by X-ray powder diffraction (XRD), Fourier transform infrared (FT-IR), Brunauer–Emmett–Teller analysis (BET) and Gas Chromatography-Mass Spectrometer (GC-MS). The desulfurization performance of this solid acid catalyst was investigated and optimized. [ABSTRACT FROM PUBLISHER]

In this work we proposed a novel preparation-adsorption desulfurization method for dibenzothiophene over sawdust-derived nickel/activated carbon prepared by 400°C one step carbonization-activation-modified process. The adsorbent was characterized by X-ray Diffraction (XRD), Boehm titration method, Scanning Electron Microscope (SEM) and N2adsorption-desorption technology. The result show that 30% HNO3aqueous solution and calcination 2 h for the 30%-NiO/AC adsorbent trend to better desulfurization performance with NiO active adsorption sites and surface oxygen-containing functional groups. After high temperature adsorption desulfurization, the sawdust-derived nickel/activated carbon occurred activation and reaming again, both the specific surface and the microspore volume have been great changed. [ABSTRACT FROM PUBLISHER]

A highly efficient extractive desulfurization system with dicarboxylic acid-based deep eutectic solvents (DESs) as extractants has been developed. A series of dicarboxylic acid-based DESs were synthesized by mixing n-butylpyridinium bromide ([BPY]Br) with different dicarboxylic acids. The extraction desulfurization performance of these DESs was investigated and optimized. [ABSTRACT FROM PUBLISHER]

In situ prepared hydrophobic CuO nanoparticles, about 84.3 nm in mean diameter, was synthesized and used to catalyze heavy oil low-temperature oxidation (LTO) reaction. Experimental results showed the average oxygen consumption rate with CuO nanoparticles addition increased by 1.4 times, and the residue oxygen content in tail gas in autoclave was decreased from 8.76% to 3.9% compared to the blank experiment (without CuO nanoparticles). In addition, the CuO nanoparticles could facilitate the cleavage reaction during LTO. This study can provide guidelines to improve effectively the safety of air flooding technology in the heavy oil. [ABSTRACT FROM PUBLISHER]

We report the structural, magnetic, and ferroelectric properties of double-perovskite Bi2FeMnO6 in which Fe3+ and Mn3+ cations are present with alternative ordering along the [111] direction. High-flux synchrotron X-ray diffraction and high resolution transmission electron microscopy show that the pseudo-cubic lattice of Bi2FeMnO6 consists of alternatively corner-shared octahedra of FeO6 and MnO6. In the highly ordered Bi2FeMnO6 thin films, the unusual spin-glassy magnetic state is observed below 18 K by a superconducting quantum interference device, and this is ascribed to the magnetic frustration at the [111] Fe3+ and Mn3+ planes as indicated by X-ray magnetic circular dichroism measurements. Combining with the orbital model analysis based on Goodenough–Kanamori–Anderson rules, first-principles calculations and Monte Carlo simulations suggest that magnetic frustration is dominated by the long-range second nearest neighboring antiferromagnetic interactions of Fe3+–Fe3+ and Mn3+–Mn3+ and leads to the surprisingly weak magnetism. On the other hand, robust room-temperature ferroelectricity in Bi2FeMnO6 films is confirmed by piezoelectric force microscopy through electrically switching the polarization state and the ferroelectric retention. [ABSTRACT FROM AUTHOR]

Diesel with S content 624.4 µg/g was directly used, and a constant current of 500 mA was proposed in this work. Emulsification as an enhancement method was used to enhance the interphase mass transfer. After emulsifying electrochemical oxidation–extraction, the sulfur content of diesel decreased to 8.1 µg/g and the desulfurization efficiency reached 98.71 %. On comparingwith the non-emulsifying electrochemical oxidation–extraction, it has a highly efficient deep desulfurization. The analysis also found that the effect of emulsion and non-emulsion extraction desulfurization process on electrochemical oxidation has great difference under the same operating conditions, and parameters such as the order, reaction rate and activation energy of the two kinds of oxidation desulfurization reaction were studied. The results showed the oxidative desulfurization reaction is the first reaction. When the temperature reachedT2, the oxidation rate constant of the emulsion/non-emulsion system was 0.0199 min−1and 0.0179 min−1, respectively. When the temperature reachedT1, the oxidation rate constant of the emulsion/non-emulsion system was 0.0375 min−1and 0.0346 min−1, respectively. According to Arrhenius' law, the apparent activation energy of sulfur compounds in the raw oil isEa(emulsion) = 6.9783 kJ/mol andEa(non-emulsion) = 9.1826 kJ/mol, respectively. [ABSTRACT FROM AUTHOR]

Air-assisted steam flooding is a new promoting technique for enhanced oil recovery compared to the other traditional thermal recovery methods. In this study, five experiments, including one steam flooding experiment, three combined steam–air flooding experiments, and one combined steam–N2flooding experiment were studied, under the conditions of 180 °C and back-pressure valve of 8 MPa, with sand-packed model. The volume fraction of mixed gas in these four combined steam–air (or N2) flooding experiments were 80% steam+20% air, 60% steam+40% air, 40% steam+60% air, and 60% steam+40% N2, respectively. The experimental results showed that air-assisted steam flooding could enhance the oil displacement efficiency when the volume fraction of air and steam was in a certain number, and the optimal condition is 60% steam+40% air. Furthermore, water cut curves and saturate, aromatic, resin, and asphaltene (SARA) analysis results also demonstrate that the low-temperature oxidation reaction in air-assisted steam flooding process advantageous to profile control of generating high viscosity “PLUG” to seal high-permeability channel in reservoir. [ABSTRACT FROM AUTHOR]

Objective To introduce a new classification of Enneking type IV pelvic tumors involving the sacrum and a corresponding system of standardized surgical approaches and procedures for resection of such tumors, and to investigate the feasibility and therapeutic effect of the new system. Methods Data on 59 patients treated between February 2003 and February 2013 by standardized surgical approaches and procedures were retrospectively reviewed. The study subjects comprised 28 male and 31 female patients with a mean age at diagnosis of 36 years (range, 2-72 years). There are four subtypes in the new classification: (i) subtype IVa, neoplasms invading the ipsilateral sacral wing; (ii) subtype IVb, neoplasms invading the ipsilateral sacral foramina; (iii) subtype IVc, neoplasms invading the contralateral sacral foramina; and (iv) subtype IVd, neoplasms invading the whole of the sacrum. Standardized surgical approaches and procedures were devised for en-bloc resection for each subtype with adequate margins. Results Adequate margins were achieved in 43/59 patients (72.9%). The mean operation time was 5.0 h and the mean intraoperative blood loss 2157 mL. At the final follow-up, 27/53 patients (50.9%) who had been followed up were alive and in complete remission. The mean Musculoskeletal Tumor Society 93 score was 17.4 (58%) of a possible 30 points. The mean functional score for patients who had undergone a pelvic zone II resection was 15.2, compared with 19.0 for those with an intact pelvic zone II. Conclusions The proposed standardized protocols should help orthopaedic surgeons to achieve adequate margins, manage risk, achieve better oncologic and functional outcomes, and minimize perioperative complications when treating massive pelvic tumors involving the sacrum. [ABSTRACT FROM AUTHOR]

An electrochemical oxidation−distillation method with constant current 500 mA was proposed to reduce the sulfur content in gasoline in this work. After electrochemical oxidation−distillation, the sulfur content of gasoline decreased from 514.65 to 10.20 μg/g. On the basis of these experimental results, an oxidation mechanism of electrochemical oxidative desulfurization for gasoline was proposed. [ABSTRACT FROM PUBLISHER]