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Synthesis of CeO_2 nanoparticles using flame-assisted spray pyrolysis and solid state diffusion routes

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Rare Metals 2015年第1期34卷 6-11页

作者： K.R.Nemade S.A.Waghuley Department of Physics Sant Gadge Baba Amravati University

The stable and crystalline phase of pure nano- structured CeO2 was directly synthesized by flame-assisted spray pyrolysis and solid state diffusion route. Different characterization techniques, including X-ray diffraction （XRD）, scanning electron microscopy （SEM）, Fourier trans- form infrared spectroscopy （FTIR）, ultraviolet-visible （UV- Vis）, and thermo gravimetric analysis （TGA） were employed to examine the structural, morphological, optical, and thermal properties of the final product. Similarly, the comparative carbon dioxide （CO2）-sensing response of as-synthesized CeO2 nanoparticles by both routes was also reported. The CeO2 nanoparticles synthesized by solid state diffusion method exhibit good sensitivity （3.38 %） at room temperature, low operating temperature （398 K）, fast response time （32 s）, and recovery time （36 s） along with good stability.

关键词： CO2 gas sensing Flame-assisted spraypyrolysis Solid state diffusion

Aldo-keto synthesis effect on Eu^(3+) fluorescence in YBO3 compared with solid state diffusion

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Journal of Rare Earths 2015年第5期33卷 486-490页

作者： K.A.Koparkar N.S.Bajaj S.K.Omanwar Department of Physics Sant Gadge Baba Amravati University

The red-orange emitting phosphor YBO3：Eu3＋was prepared by aldo-keto method and solid state diffusion. Aldo-keto method implied to decrease the processing time and heating temperature. The red-orange emitting phosphor was characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, as well as emission and excitation photoluminescence spectra re-corded at room temperature. The result of aldo-keto method showed that the phosphor YBO3：Eu3＋could be obtained at 900 °C in less time^60%as compared to solid state diffusion （SSD）. The material showed that the strongest emission peak at 595 nm under excitation at 233 nm was only due to forced magnetic dipole 5D0→7F1 transition of Eu3＋ions. Significantly, the emission inten-sity of YBO3：Eu3＋phosphor prepared by aldo-keto method was relatively higher as compared to that obtained by the solid state diffusion.

关键词： aldo-keto method yttria europium optical materials photoluminescence (PL) rare earths

Gossypibomas as a rare cause of common bile duct dilation

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Hepatobiliary & Pancreatic Diseases International 2019年第5期18卷 498-500页

作者： Raffaele Pezzilli Paula A.Mauloni Nico Pagano Department of Gastroenterology Sant’Orsola Hospital

Gossypibomas are any foreign bodies left inside the patient after an operation. It represents a diagnostic challenge in clinical practice because the clinical consequence may manifest in different forms immediately, m... 详细信息

关键词： Gossypibomas common bile duct dilation clinical consequence

Serum tumor markers not useful in screening patients with pancreatic mucinous cystic lesions associated with malignant changes

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Hepatobiliary & Pancreatic Diseases International 2016年第5期15卷 553-557页

作者： Raffaele Pezzilli Lucia Calculli Gianvico Melzi d'Eril Alessandra Barassi Department of Digestive System Sant’Orsola-Malpighi Hospital Department of Radiology Sant’Orsola-Malpighi Hospital Department of Health Sciences SanPaolo HospitalUniversity of Milan

BACKGROUND: Serum cancer antigen 19-9 (CA19-9) pro-vides additional information about mucinous cystic pancre-atic neoplasm (MPN). This study was undertaken to assess both CA19-9 and carcinoembryonic antigen (CEA) serum concentrations in consecutive patients affected by MPNs and other chronic benign and malignant pancreatic diseases. We also evaluated whether serum CA19-9 and CEA determina-tions provide additional information such as the presence of invasive carcinoma in MPN patients. METHODS: Serum CA19-9 and CEA from 91 patients with pancreatic diseases were tested by commercially available kits at the time of diagnosis. The upper reference limit of serum CA19-9 was 37 U/mL and that of serum CEA was 3 ng/mL. RESULTS: Thirty-ifve patients was diagnosed with chronic pancreatitis (CP), 32 with MPN, and 24 with pancreatic ductal adenocarcinoma (PDAC) conifrmed histologically. Surgery was carried out in 5 CP patients, in 10 MPN patients (7 of them had severe dysplasia), and 9 PDAC patients. Serum CA19-9 activity was high in 12 (34.3%) CP patients, in 7 (21.9%) MPN patients, and in 12 (50.0%) PDAC patients (P=0.089). High se-rum CEA concentrations were noted in 6 (17.1%) CP patients, in 6 (18.8%) MPN patients, and in 12 (50.0%) PDAC patients (P=0.010). In the 7 MPN patients associated with histological-ly conifrmed severe dysplasia, 3 (42.9%) patients had elevated serum activity of serum CA19-9, and 2 (28.6%) patients had high levels of CEA. CONCLUSION: Serum determination of oncological markers is not useful in selecting MPN patients with malignant changes.

关键词： cancer antigen 19-9 carcinoembryonic antigen cystic pancreatic neoplasms chronic pancreatitis pancreatic ductal adenocarcinoma laboratory assessment

Kinetic Energy Recovery from the Chimney Flue Gases Using Ducted Turbine System

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Chinese Journal of Mechanical Engineering 2017年第2期30卷 472-482页

作者： Harjeet S.Mann Pradeep K.Singh Department of Mechanical Engineering Sant LongowalInstitute of Engineering and TechnologyLongowalPunjab 148106India

An innovative idea of extracting kinetic energy from man-made wind resources using ducted turbine system for on-site power generation is introduced in this paper. A horizontal axis ducted turbine is attached to the top of the chimney to harness the kinetic energy of flue gases for producing electricity. The turbine system is positioned beyond the chimney outlet, to avoid any negative impact on the chimney performance. The convergentdivergent duct causes increase in the flue gas velocity and hence enhances the performance of the turbine. It also acts as a safety cover to the energy recovery system. The results from the CFD based simulation analysis indicate that sig- nificant power 34 kW can be harnessed from the chimney exhaust. The effect of airfoils NACA4412 and NACA4416 and the diffuser angle on the power extraction by the energy recovery system using a 6-bladed ducted turbine has been studied with the CFD simulation. It is observed that the average flue gas velocity in the duct section at the throat is approximately twice that of the inlet velocity, whereas maximum velocity achieved is 2.6 times the inlet velocity. The simulated results show that about power may be extracted from the chimney flue gases of 660 MW power plant. The system can be retrofitted to existing chimneys of thermal power plants, refineries and other industries.

关键词： Chimney flue gases Energy recovery system ·Kinetic energy Ducted turbine CFD

Influences of a New Admixture MX on Concrete Durability

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Journal of Wuhan University of Technology(Materials Science) 2005年第1期20卷 117-120页

作者：马保国 Key Laboratory of Silicate Materials Science and Engineering Ministry of Educa tion Wuhan University of TechnologyWuhan 430070China

The performance of concrete with a new admi xt ure MX was studied by using the freeze-thaw cycle, permeability and chemical at tack test. The experimental results show that MX improves the durability of conc re te. Within the optimum proportion ranges from 0.1%to 1%,the compressive strength of concrete after freeze-thaw is increased by 20%-50%,and Young's modulus can be increased by 3.76-5.64 *** strength and weight loss of concrete with 0.4%MX are respectively decreased by 28% and 60% after hydrochloric acid attack. The strength and weight loss of concrete with 0.4% MX are decreased by 5%-20% a fter sulfuric acid and sodium sulfate *** permeability of concrete with 1 % MX at 28 days can be decreased by more than 30%. The investigation of the nega tive temperature property of MX and analysis on concrete composition and microst ructure by MIP reveal that the heat conduction is resisted and the freezing proc edure of solution in concrete pore is retarded due to the adding of MX. Moreover ,the pore structure of concrete with MX is improved, thus improving the durabili ty. Based on this study, a resistance model of MX to block the heat and mass tra nsference was proposed, and the mechanism of durability improvement of concrete with MX was explained.

关键词： MX durability admixture ratio of strength loss negative temperature property

Extension of pilot tests of cyanide elimination by ozone from blast furnace gas washing water through Aspen Plus based model

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Frontiers of Chemical Science and Engineering 2018年第4期12卷 718-730页

作者： Ismael Matino Valentina CoHa Teresa A.Branca Scuola Superiore sant' Anna TeCIP Institute-ICT-COISP56124 PisaItaly

For improving wastewater quality, one of the dare of steelworks is reducing cyanide in wastewater of gas washing treatment of blast furnaces. Costs of existing treatments, stringent environmental regulations and changeable composition of water from gas treatment, have led to study how available treatments can be modified and to examine new ones. Ozonation is one of cyanide treatments, tested within a European project. A process model was set up with Aspen Plus (R), to assess operating conditions and wastewater distinctive characteristics and to demonstrate treatment robustness. Process was modeled by theoretical reactors, taking into account all more affecting reactions. A genetic algorithm was exploited to find kinetic parameters of these reactions. After validation, the model was used to analyse scenarios, by considering also real contexts. Pilot tests were extended, process knowledge was enhanced and suggestions were obtained. To promote cyanide removal with ozone, temperature and pH values were 30 degrees C and 10, respectively. With an ozone (mg/h)/ water (L/h) ratio of 100 mg/L, batch mode ensure reaching cyanide regulation limit (0.2 mg/L) after maximum 4.5 h, if initial amount was less than 20 mg/L. Higher removal was obtained than in continuous mode due to constraints related to this last run. Higher wastewater contamination needed further time and more ozone.

关键词： blast furnace cyanide removal gas washing water modeling and simulation ozonation

Typical and atypical COVID-19 computed tomography findings

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World Journal of Clinical Cases 2020年第15期8卷 3177-3187页

作者： Damiano Caruso Tiziano Polidori Gisella Guido Matteo Nicolai Benedetta Bracci Antonio Cremona MartaZerunian Michela Polici Francesco Pucciarelli Carlotta Rucci Chiara De Dominicis Marco Di Girolamo Giuseppe Argento Daniela Sergi Andrea Laghi Department of Surgical and Medical Sciences and Translational Medicine “Sapienza”-University of RomeSant'Andrea University HospitalAOU Sant’AndreaRome 00189Italy

In December 2019 a novel coronavirus,named severe acute respiratory syndrome coronavirus 2 was identified and the disease associated was named coronavirus disease 2019(COVID-19).Fever,cough,myalgia,fatigue associated to dyspnea represent most common clinical symptoms of the *** reference standard for diagnosis of severe acute respiratory syndrome coronavirus 2 infection is real time reverse-transcription polymerase chain reaction test applied on respiratory tract *** of lower specificity,chest computed tomography(CT),as reported in manifold scientific studies,showed high sensitivity,therefore it may help in the early detection,management and follow-up of COVID-19 *** affected by COVID-19 pneumonia usually showed on chest CT some typical features,such as:Bilateral ground glass opacities characterized by multilobe involvement with posterior and peripheral distribution;parenchymal consolidations with or without air bronchogram;interlobular septal thickening;crazy paving pattern,represented by interlobular and intralobular septal thickening surrounded by ground-glass opacities;subsegmental pulmonary vessels enlargement(>3 mm).Halo sign,reversed halo sign,cavitation and pleural or pericardial effusion represent some of atypical findings of COVID-19 *** the other hand lymphadenopathy’s and bronchiectasis’frequency is unclear,indeed conflicting data emerged in *** play a key role in recognition of high suspicious findings of COVID-19 on chest CT,both typical and atypical ***,the aim of this review is to illustrate typical and atypical CT findings of COVID-19.

关键词： SARS-CoV-2 COVID-19 Chest computed tomography Interstitial pneumonia Ground-glass opacities

New Role for an Old Rule: N-end Rule-Mediated Degradation of Ethylene Responsive Factor Proteins Governs Low Oxygen Response in Plants

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Journal of Integrative Plant Biology 2013年第1期55卷 31-39页

作者： Francesco Licausi Chiara Pucciariello Pierdomenico Perata Plant Lab Institute of Life Sciences Scuola Superiore Sant' Anna

The N-end rule pathway regulates protein degradation, which depends on exposed N-terminal sequences in prokaryotes and eukaryotes. In plants, conserved and specific enzymes stimulate selective proteolysis. Although a number of developmental and growth phenotypes have been reported for mutants in the N-end rule, its function has remained unrelated to specific physiological pathways. The first report of the direct involvement of the N-end rule in stress responses focused on hypoxic signaling and how the oxygen-dependent oxidation of cystein promotes the N-end rule-mediated degradation of ethylene responsive factor （ERF）-VII proteins, the master regulators of anaerobic responses. It has been suggested that plants have evolved specific mechanisms to tune ERF-VII availability in the nucleus. In this review, we speculate that ERF-VII proteins are reversibly protected from degradation via membrane sequestration. The oxidative response in plants subjected to anoxic conditions suggests that reactive oxygen and nitrogen species （reactive oxygen species and reactive nitrogen species） may interact or interfere with the N-end rule pathway-mediated response to hypoxia.

关键词： Ethylene response factor flooding hypoxia N-end rule pathway ubiquitin.