bluuebunny/crossref_metadata_2025 huggingface dataset:
Split-bolus contrast injection protocol enhances the visualization of the thoracic vasculature and reduced radiation dose during chest CT
Authors: Zein-El-Dine Salah , Bou Akl Imad , Mohamad Maha , Chmaisse Ahmad , Chahwan Stephanie , Asmar Karl , El-Merhi Fadi , Saade Charbel
Published: August 2018

Objective

To investigate the visualization of mediastinal lymph nodes during thoracic CT employing a multiphasic contrast media (CM) protocol.

Methods

Institutional review board approved retrospective study consisting of 300 patients with known chest malignancy. Patients were allocated to one of two CM protocols: Protocol A, consisted of dual bolus (Phase 1:100 ml CM followed by 100 ml saline chaser) i.v. injected at 2.5 ml s−1; Protocol B employed 100 ml of CM using a multiphasic injection protocol (Phase 1 and 2:60 ml contrast and saline, followed by Phase 3 and 4:40 ml contrast and saline injected at 2.5 ml s−1) with a fixed scan delay of 70 s for each acquisition. Attenuation profiles of the thoracic arteries and veins were calculated as well as the arterio-venous contrast ratios (AVCR). Receiver operating characteristic (ROC), visual grading characteristic (VGC), and Cohen's kappa analysis were assessed.

Results

Arterial opacification was up to 24% (p < 0.032) higher in protocol B than A, whereas, in the veins it was significantly lower in protocol B than A, with a maximum reduction of up to 84% (p < 0.0001). There was no statistical significance between the central and peripheral pulmonary arteries [>263 Hounsfield units (HU)] in each protocol. Protocol B, demonstrated significant improvement in AVCR at various anatomical sites (p < 0.002). Radiation dose was significantly reduced in protocol B compared to A (p < 0.004). Both ROC and VGC demonstrated significantly higher Az score for protocol B compared to A (p < 0.0001) with an increased inter reader agreement from poor to excellent.

Conclusion

Employing a multiphasic CM protocol significantly improves opacification of the thoracic vasculature and visualization of mediastinal lymph nodes during thoracic CT.

Advances in knowledge

Uniform opacification between thoracic arteries and veins increases the delineation between vasculature and lymph nodes, reduces radiation dose when employing a multiphase contrast media injection protocol.
Environmental variation obscures species diversity in southern European populations of the moss genus Ceratodon
Authors: Nieto-Lugilde Marta , Werner Olaf , McDaniel Stuart F. , Ros Rosa M.
Published: August 2018

A major problem in taxonomy is to determine if morphological variation in field–collected specimens is caused by genetic differentiation, and therefore corresponds to evolutionary distinct units, or is caused by environmental variation acting on a single interbreeding population. To evaluate the effect of environmental variation on the taxonomy of the moss genus Ceratodon, we compared biometric analyses based on 22 morphological characters on both field–collected plants and cultivated plants to a clustering based on DNA sequence and genome size data published previously. We sampled Ceratodon species from mountainous areas of the Mediterranean region, and other mountain regions and lowlands, mostly from southern Europe. We found that the expression of several gametophytic traits changed between field and laboratory conditions, confirming that environmental variability complicates taxonomic inferences, and suggesting that some characters should be used with caution in distinguishing among species. However, consistent with the genetic and flow cytometry data, we found a clear biometric discontinuity between some plants collected from southern Spain, and those from other parts of the world. Samples considered of hybrid origin, based on genetic data, were morphologically indistinguishable from plants from the southern Spanish mountains. Integrative taxonomy based on genetic, genome size and morphological data unambiguously support the recognition of a new species, Ceratodon amazonum. These data also suggest that the previously recognized C. conicus is a recombinant between C. amazonum and C. purpureus and is considered here to be a nothospecies, for which an epitype is designated because the lectotype is demonstrably ambiguous.
DSM-5 paraphilic disorders criteria in the light of autoerotic asphyxiophilia and non-sexual form of oxygen restriction
Authors: Dora Marta , Mijas Magdalena , Dobroczyński Bartłomiej
Published: August 2018

Opublikowana w 2013 roku piąta wersja klasyfikacji DSM (Diagnostic and Statistical Manual of Mental Disorders) okazała się szczególnie interesująca w części poświęconej seksualności. Wprowadzono szereg istotnych zmian w sposobie definiowania normy seksualnej, m.in. szeroko komentowane rozróżnienie pomiędzy parafilią a zaburzeniami parafilnymi. Kluczowymi kryteriami odróżniającymi atypowe preferencje seksualne od wymagających interwencji zaburzeń, są teraz: istotne klinicznie cierpienie wynikające bezpośrednio z posiadanej preferencji i/lub ryzyko doznania lub sprawienia krzywdy innej osobie na skutek realizacji tej preferencji. W przypadku masochizmu – nieodłącznie związanego z bólem lub cierpieniem, tak zaproponowane rozróżnienie wzbudza szereg wątpliwości. Posługując się przykładem asfiksji autoerotycznej - zachowania znajdującego się w spektrum praktyk masochistycznych - autorzy krytycznie przyglądają się proponowanej w DSM-5 definicji normy odnoszącej się do preferencji seksualnych. Interesujące w tym aspekcie jest porównanie asfiksji autoerotycznej do swobodnego nurkowania (free diving) - pozaseksualnej aktywności, która nie jest patologizowana, mimo podobnego ryzyka utraty zdrowia i życia na skutek pozbawienia dostępu do tlenu.
Agregação de comportamentos de risco à saúde de escolares da rede pública de Jequié, Bahia, Brasil
Authors: Munaro Hector Luiz Rodrigues , Silva Diego Augusto Santos , Lopes Adair da Silva
Published: August 2018

O objetivo deste estudo foi estimar as prevalências de comportamentos de risco à saúde, de forma isolada e agregada, e analisar fatores associados. Tratou-se de estudo epidemiológico transversal, com amostra representativa de escolares de 14 a 20 anos de idade (n = 1.170) do ensino médio da rede pública, Jequié, Bahia, Brasil. Os comportamentos de risco observados foram: níveis insuficientes de atividade física, comportamento sedentário, consumo inadequado de frutas e verduras e consumo de bebidas alcoólicas e de tabaco. Os possíveis fatores associados foram: sexo, idade, estado civil, ocupação, escolaridade da mãe e renda familiar. A prevalência de nível insuficiente de atividade física foi mais elevada no sexo feminino (87,6% vs. 73,0%; p = 0,001), enquanto que o consumo de bebidas alcoólicas (28,2% vs. 20,6%; p = 0,003) e de tabaco (8,7% vs. 3,8%; p = 0,001) foi superior no masculino. Para o sexo feminino houve 6,34 vezes maior a prevalência observada pela esperada (PO/ PE), entre: níveis insuficientes de atividade física, comportamento sedentário e consumo de bebidas alcoólicas e de tabaco A prevalência de três ou mais comportamentos de risco foi de 7,9% (IC95%: 6,4-9,5) e os escolares que pertenciam às famílias com renda inferior a dois salários mínimos tiveram menor probabilidade de exposição (RP = 0,60; IC95%: 0,39-0,93). Os resultados indicaram elevada prevalência de insuficientemente ativos, de consumo inadequado de frutas e verduras e agregação de múltiplos comportamentos de risco para o sexo feminino.
Exclusive Placement in Online Advertising
Authors: Sayedi Amin , Jerath Kinshuk , Baghaie Marjan
Published: August 2018

A recent development in online advertising has been the ability of advertisers to have their ads displayed exclusively on (a part of) a web page. We study this phenomenon in the context of both sponsored search advertising and display advertising. Ads are sold through auctions, and when exclusivity is allowed, the seller accepts two bids from advertisers, where one bid is for the standard display format in which multiple advertisers are displayed, and the other bid is for being shown exclusively (therefore they are called two-dimensional, or 2D, auctions). We identify two opposing forces at play in an auction that provides the exclusive placement option—allowing more flexible expression of preferences through bidding for exclusivity increases competition among advertisers, leading to higher bids, which increases the seller’s revenue (between-advertiser competition effect), but it also gives advertisers the incentive to shade their bids for their nonpreferred outcomes, which decreases the seller’s revenue (within-advertiser competition effect). Depending on which effect is stronger, the revenue may increase or decrease. We find that the 2D generalized second price (GSP2D) auction, which is an extension of the widely used generalized second price (GSP) auction and on which currently used auctions for exclusive placement are based, may lead to higher or lower revenue under different parametric conditions. Paradoxically, the revenue from allowing exclusive placement decreases as bidders have higher valuations for exclusive placement. We verify several key implications from our analysis of GSP2D using data from Bing for over 100,000 auctions. As a possible solution (applicable to both sponsored search and display advertising), we show that using VCG2D, which is the adaptation of the Vickrey–Clarke–Groves (VCG) auction for the 2D setting, guarantees weakly higher revenue when exclusive display is allowed. This is because it induces truthful bidding, which alleviates the problem of bid shading due to the within-advertiser competition effect.

The online appendix is available at https://doi.org/10.1287/mksc.2018.1098 .
Smoothies: Exploring the Attitudes, Beliefs and Behaviours of Consumers and Non-Consumers
Authors: McCartney Danielle McCartney , Rattray Megan , Desbrow Ben , Khalesi Saman , Irwin Christopher
Published: August 2018

Smoothies are popular dietary products. An online survey of Australian adults (n=833; 79% female) was used to explore patterns of smoothie consumption and individual motives for consuming these beverages. Participants commonly reported consuming fruit (98%), yoghurt (66%), milk (58%), honey (52%), fruit juice (46%), and nutritional supplements (46%) in smoothies. Compared to Infrequent Smoothie-Consumers (I-SC, < 1•week-1; n=514), Frequent Smoothie-Consumers (F-SC, >= 1•week-1; n=269) were more likely to consume core-foods (e.g. vegetables, p < 0.001) and less likely to consume discretionary items (e.g. honey or ice-cream, p’s < 0.020) in smoothies. It followed that F-SC typically cited “health-related reasons” for consuming these beverages (i.e. to increase fruit/vegetable [57%] or nutrient [50%] intake, and/or to be “healthy” [56%]) and perceived these products as “nutritious” (84%); whilst I-SC often perceived them as “indulgent” (62%). Smoothies may play a positive role in the diet. However, beverages incorporating discretionary choices may increase energy, saturated fat and/or sugar intakes, offsetting the benefits of fruit/vegetable consumption.
Microbiological Evaluation and Storage Stability of Snakehead Fish Extract (Channa striata) using Steaming Method
Authors: Hidayati Dewi , Jadid Nurul , Nugroho Endry , Abdulgani Nurlita , Hidayatul Alami Nur , Ayu Cahyaning Putri Dyah
Published: August 2018

The snakehead fish (SHF) has commercial value due to its health benefit. Steaming extraction method using distilled water within temperature below 60°C is the one of extraction methods to obtaining the SHF extract with high yield of valuable soluble protein albumin, as well as relatively simple to applied at home industries. Recently, the recommended storage for these conventional steamed SHF extract (SSHFE) product is in freeze temperature (-20°C), not in room temperature. Evaluation to find scientific reason related to the SSHFE storage stability is necessary required. The series of storage stability and microbiological test toward SSHFE had investigated included total plate count (TPC); most probable number (MPN) of coliform and Eschericia coli test using Gram staining and Indol, Methyl Red, Voges Praskauer, Citrate (IMVIC) at different storage stability treatments. This research found that SHF extract during storage of 0 week after out from freezer were negatively contaminated (TPC <= 102 CFU/ml). While, TPC at storage of 1; 4; 8 weeks after out from freezer showed contamination in level of 1.722x103 CFU/ml; 1.327x104. CFU/ml and 6.839x104 CFU/ml, respectively which still below threshold that stipulated by Indonesian Food Standardization (5x105 CFU/ml). While MPN index were exceed the standard, i.e. 24/g (1 week), 350/g (4 weeks), and < 1600/g (8 weeks). Moreover, the gram stain and IMVIC test indicated that they were positively contaminated by Eschericia coli. Accordingly, SSHFE is recommended to store at freeze temperature and immediately consumed after melt in room temperature. Further research of sterilizing methods for SSHFE processing is suggested.
Micro-Mineral Retention and Anti-Nutritional Compounds Degradation During Bean Cooking Process
Authors: Patrick Ongol Martin , Owino Joseph , Lung’aho Mercy , Dusingizimana Théogéne , Vasanthakaalam Hilda
Published: August 2018

The objective of this study was to determine the effect of soaking, boiling and frying on retention of micro-minerals as well as degradation of polyphenols and phytic acids. Soaking of the beans did not significantly (p > 0.05) decrease mineral, total polyphenol and phytic acid content of beans. While boiling of beans significantly (p < 0.05) decreased the concentration of total polyphenols and phytic acid but not the mineral content of the beans. Frying of boiled beans decreased the total polyphenol content but increased the concentration of phytic acids in beans. Data obtained in this study indicates that cooking of beans without discarding of soaking water and broth results into greater retention of minerals but frying may be detrimental to mineral bioavailability because it leads to increase in phytic acid content.
Study of the National Cooked Smoked Meat Products While Tests with Laboratory Animals at the Pathology Models with the Purpose to Confirm the set of Biocorrective Features
Authors: Makangali Kadyrzhan , Taeva Aigul , Lisitsyn Andrei , Uzakov Yasin , Konysbaeva Damilya , Victoria Gorbula
Published: August 2018

Conducted physico-chemical and biological studies of Goji berries and national products made it possible to obtain information on the bioavailability of nutrients included in the product, to evaluate their food value and nutritional value, and their functional orientation. The study of the processes of digestibility and absorption of the developed products on the gastric invitro model and the monolayer of the intestinal wall epithelium showed high absorption and assimilability of the low molecular weight (from 30 kDa and below) protein fraction of the studied product. The detected acceleration of the absorption of nutrients of the tested products was reflected positively on the dynamics of changes in the biochemical composition of the blood, which, in turn, will lead to an acceleration of the biocorrecting action of functional biologically active substances. As a result of the experiment it was established that Goji berries, characterized by high catalase activity, have a prominent antioxidant effect, helping to control free radical oxidation in the rat organism with hyperlipidemia by decrease of MDA concentration (to 30%) and improvement of blood serum antioxidant activity (to 40 %). A prominent hipolipidemic (lipid-lowering) effect of berries has been established, which consists in normalization of the blood serum lipid profile of rats with hyperlipidemia 28 days after the beginning of feeding (decrease in total cholesterol (by 1.5 times), low density lipoproteins (to 40%) and blood serum atherogenity index (by more than 50%) with increase of high-density lipoproteins (up to 45%).
Effect of ZnSO4 and MnSO4 on the Growth of Sulphamic Acid Single Crystals
Authors: Anupriya K.G. , Hemalatha P.
Published: August 2018

Single crystals of Sulphamic Acid doped with Zinc Sulphate and Manganese Sulphate were grown at room temperature using slow evaporation technique. Structural analysis of the grown crystals was done using single crystal X Ray Diffraction and powder X Ray Diffraction studies. Various functional groups seen in the grown crystals are determined using FTIR spectroscopic analysis. The cut-off wavelength of ZnSO4 and MnSO4 doped Sulphamic acid were evaluated by UV-Vis-NIR spectral studies. Thermal behaviour of the grown crystals was identified from Thermogravimetric Analysis (TGA) and Differential Thermogravimetric Analysis (DTA). The mechanical strength and Second harmonic generation of the grown crystals was identified by Vicker’s Microhardness Test and Kurtz powder technique respectively.
Exploration of Thread for their Possible use in Fabrication of Low Cost Diagnostic Microfluidic Device
Authors: B Kabariya Rakesh , M Ramani Vimal
Published: August 2018

The emerging concept of thread-based microfluidics has shown great promise for application to inexpensive disease detection and environmental monitoring. This paper describe the properties of thread for the development of thread based low-cost microfluidics device for the diagnostic, food safety and environmental assay. Various properties of thread like capillary flow, wicking capacity and absorption capacity, make them important to fabricate the low-cost microfluidics device. In this paper, three different thread sample viz. cotton yarn, cotton thread and spun thread were taken and different properties like wicking capacity, fluid capillary flow, absorption capacity were measured as well as Scanning Electron Microscopic (SEM) analysis of the same was also carried out to study the morphology and texture of thread fibers. Data obtained from result indicate that the cotton thread having all the ideal characteristic to fabricate the diagnostic device and thus it is suitable for the fabrication of thread based microfluidics device for the diagnostic purpose.
Hydrothermal Preparation of Silver Doping Zinc Oxide Nanoparticles: Studys, Characterization and Photocatalytic Activity
Authors: A. Habeeb Alshamsi Hassan , S. Hussein Batool
Published: August 2018

In this study , we report the prepared of ZnO nanoparticles and Ag doped ZnO nanostructure via a hydrothermal process. The obtained nanostructures were characterized using different characterization techniques such as X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) , atomic force microscopy (AFM) ,Fourier transform infrared spectrometry (FTIR)and UV/Visible spectrophotometer.The XRD results showed the wurtzite hexagonal structure of the ZnO Nanoparticles. Furthermore, the morphology of ZnO and Ag-ZnO nanostructures was obtained from SEM and AFM. The photocatalytic degradation of Cibacron Brilliant Yellow 3G-P (CB) dye was studied in presence of visible light using Ag-ZnO nanostructures as a photocatalyst. There are numerous factors which has an effect on the efficiency color removal of this process. Hence a study was conducted on the effect of several parameters on Ag-ZnO like amount of catalyst, CB dye concentration and pH of solution. Results showed Ag doping ZnO with 3% loading shows photocatalytic removal about 65% after 120 min which influenced superior photocatalytic activity than pure ZnO.
Preparation and Characterization of Chloride-Free Alumina-Supported Platinum Catalysts
Authors: Kolonial Prodjosantoso Anti
Published: August 2018

Supported precious metal catalysts are extensively used as efficient catalysts. This kind of catalysts, particularly chloride-free catalysts, sintesized using organoplatinum compounds as precursors has attracted immense research interest compared to their parent metals due to their unique physico-chemical properties. The main objective of this research is to prepare and characterize the chloride-free alumina-supported platinum catalysts. An organometallic compound of ammonium bisoxalatoplatinate(II) hydrate was used to prepare unsupported and alumina supported platinum catalysts. A series method including IR, XRD, SEM, TEM, EDA, and XPS was used to characterize samples. The research shows that ammonium bisoxalatoplatinate(II) hydrate could be synthesized and used to prepare unsupported and alumina supported platinum free of chloride impurities.
Variations in Non-enzymatic Antioxidants in Hisar Arun (Local) and Kashi Vishesh (Hybrid) Cultivars of Tomato Fruits Treated with H2O2 during storage periods
Authors: Mishra Saumya , Prakash Veeru
Published: August 2018

Alterations in non-enzymatic antioxidants of tomato fruits of two cultivars (Kashi Vishesh: a local & Hisar Arun: a hybrid) during their storage were studied. Tomatoes, harvested at mature green, breaker, and mature red stages were treated with 1% and 4% solution of H2O2 and then kept at storage temperatures 5°C,10°C, and 15°C. Antioxidant activity, ascorbic acid, carotenoids, Lycopene and total phenol content were measured after every 7-day interval up to a total storage duration of 21 days. The recorded non-enzymatic characteristics shown an increase upto 14 days and then started declining irrespective of storage temperature and concentration of H2O2 treatment and maximum change was seen at15°C and 1% H2O2. On the other hand, lycopene content increased asymptotically at all maturity stages and at all storage temperatures which is suggestive of slowing ripening process. In conclusion, local cultivar, harvested at mature green stage, showed slowest increase rate in antioxidants activities when treated with 1% H2O2 and stored at 5°C.
Retrograde Amnesia and Disorientation after Intraocular Injection of Anti-VEGF Agents
Authors: Meyer Peter-Wolfgang , Ungerer Matthias N. , Schröder Johannes
Published: August 2018

We present a case of a 77-year-old male patient who was treated in our outpatient clinic for memory disorders because of episodic confusion and retrograde amnesia. The patient reported having symptoms repeatedly following intraocular treatment with Anti-Vascular Endothelial Growth Factor Agents (Ranibizumab and Bevacizumab) as a treatment for wet macular degeneration. EEG showed a localized deceleration that intensified under prolonged voluntary hyperventilation. Symptoms resolved after the intraocular Anti-Vascular Endothelial Growth Factor treatment was stopped and anticonvulsive treatment with lamotrigine was begun. This case is important in that it describes a potential association between intraocular treatments with Anti-Vascular Endothelial Growth Factor Agents and seizures. Symptoms occurred in temporal correlation with intraocular treatment. Clinicians should be aware of this potential side effect on intraocular treatment with Anti-Vascular Endothelial Growth Factor Agents in patients with high risk for seizures.
Pt-CeOx/MWCNT electrocatalysts as ethanol-tolerant ORR cathodes for Direct Alcohol Fuel Cells
Authors: Varela F. J. Rodriguez , Coronado A. A. Gaona , Loyola J. C. , Jiang Qi-Zhong , Perez P. Bartolo
Published: August 2018

High performance 20% Pt-CeOx (1:1 Pt:Ce weight ratio) electrocatalyst dispersed on Multiwalled Carbon Nanotubes (MWCNTs) was synthesized under H2 atmosphere at 300 °C. The average particle size determined from XRD was ca. 1.7 and 10 nm for Ce and Pt, respectively. HRTEM analysis confirmed the presence of particle sizes within this range, although it was not possible to distinguish Ce from Pt nanoparticles. The XPS spectrum of Ce showed characteristics that indicate the existence of both oxidized and reduced phases (i.e., Ce2O3 and CeO2). It is suggested that the presence of the C3+ state establishes the capacity of this material to act as a tolerant cathode. The spectrum of Pt confirmed the presence of Pt metal. The 20% Pt-CeOx/MWCNT cathode showed high electroactivity for the Oxygen Reduction Reaction (ORR). Moreover, this novel material presented a high degree of tolerance to ethanol. During polarization tests in ethanol-containing solution, the Pt-CeOx/MWCNT cathode showed no peak current density due to the ethanol oxidation reaction (EOR) and the onset potential for the ORR shifted by only 80 mV towards more negative potentials. Thus, the presence of ceria clearly enhanced the electrochemical tolerance of the Pt-based cathode to ethanol.
Ni/ZrO2-CeO2 Catalysts for the Simultaneous Production of Hydrogen and Carbon Nanotubes
Authors: Hernandez-Pichardo M. L. , Valenzuela M. A. , Paredes S. P. , Del Angel P. , De la Fuente J. A. Montoya
Published: August 2018

The catalytic methane decomposition (CMD) using Ni/ZrO2-CeO2 catalysts for the simultaneous production of hydrogen and carbon nanotubes, was studied on samples prepared by different synthesis methods. The catalysts were synthesized by the impregnation and coprecipitation methods with or without ultrasound treatment. X-ray diffraction (XRD), Raman spectroscopy and high resolution transmission electron microscopy (HRTEM) were the main characterization techniques. It was observed that the Ni impregnated catalyst with ultrasound treatment increases significantly the production of hydrogen and carbon nanotubes in the CDM at 500 °C. The results also indicated that the synthesis of catalysts via coprecipitation generates a higher number of encapsulated Ni particles by both, the ZrO2-CeO2 support and the produced carbon at the end of the reaction.
Fuel Cell Characteristics of the Membrane Electrode Assemblies using Phosphoric Acid-doped Poly[2,2’-(p-oxydiphenylene)-5,5’-bibenzimidazole] Membranes
Authors: Fang Liang , Sheng Li , Guo Xiaoxia , Fang Jianhua , Ma Zi-Feng
Published: August 2018

The membrane electrode assemblies (MEAs) based on phosphoric acid (PA)-doped poly[2,2’-(p-oxydiphenylene)-5,5’-bibenzimidazole] (OPBI) membranes were prepared for the high temperature polymer electrolyte membrane fuel cells, and the moderate molecular weight poly[2,2’-(m-phenylene)-5,5’-bibenzimidazole] (mPBI) with good solubility in aprotic solvents was synthesized and utilized as the binder in catalyst layers for the first time. The hot press and the components in catalyst layers that affected the performances of MEAs were studied. The cell performance evaluation and electrochemical impedance spectroscopy were carried out at temperatures ranging from 80 to 160 °C in a single cell setup. It was found that the prepared OPBI and the moderate molecular weight mPBI with high solubilities of polybenzimidazole could facilitate and simplify the preparation of MEAs. The novel MEAs using the PA-doped OPBI membranes and moderate molecular weight mPBI exhibited good performances in the polarization tests, constant current tests, and temperature cycle tests, which were comparable with those traditional MEAs using the PA-doped mPBI.
Electrochemical Corrosion of Al-Li-Sn Alloy in Water for Portable Hydrogen Sources Effect of Aluminum
Authors: Liu Shu , Fan Mei-qiang , Chen Da , Lv Chun-Ju
Published: August 2018

The hydrogen generation of milled Al−Li−Sn alloy in water as a portable hydrogen source was examined in the current study. The optimized alloy composition presented significant improvement in terms of hydrogen generation rate and amount, with their values respectively reaching 1137 mL g-1 min-1 and 1147 mL g-1 with an increase in Li/Sn weight ratio from 1:7 to 1:1. The efficiency of the alloy composition increased up to 99% with approximately 3.4 wt% hydrogen storage amount obtained. The XRD results indicated that the improved aluminum hydrolysis properties were attributed to the formation of the Li−Sn alloy, especially to the complex intermetallic compound Li13Sn5 produced with an increase in Li/Sn weight ratio. The Li−Sn alloy referred to an active site that acted as the initial hydrolysis center, and its hydrolysis byproduct, LiOH, can further stimulate the hydrolysis of the Al−Sn alloy.
Structure and Electrochemical Performance of LiNi0.8Co0.15Al0.05O2 Cathodes Before and After Treatment with Co3(PO4)2 or AlPO4 by in situ Chemical Method
Authors: Bak Yu-Rim , Chung Youngmin , Ju Jeong-Hun , Hwang Moon-Jin , Lee Youngil , Ryu Kwang-Sun
Published: August 2018

Co3(PO4)2 or AlPO4 coating layers were formed on the surface of LiNi0.8Co0.15Al0.05O2 cathode material by in situ chemical method and calcination at 700°C to improve the electrochemical cyclability and structural stability during charge-discharge process of the cathode. The structure and electrochemical properties of the pristine LiNi0.8Co0.15Al0.05O2 cathode materials and the metal phosphate coated-cathode materials were investigated by X-ray powder diffraction, scanning electron microscopy, particle size analysis, Brunauer-Emmett-Teller method, cyclic voltammetry, and galvanostatic charge-discharge test. Co3(PO4)2-LiNi0.8Co0.15Al0.05O2 and AlPO4- LiNi0.8Co0.15Al0.05O2 cathode showed the improved reversibility compared with the pristine cathode material. It is attributed to the structural stability of metal phosphate coated LiNi0.8Co0.15Al0.05O2. In particular, Co3(PO4)2-LiNi0.8Co0.15Al0.05O2 showed a more stable rate capability than the pristine LiNi0.8Co0.15Al0.05O2 and AlPO4-LiNi0.8Co0.15Al0.05O2 at high C-rate.
Electrochemical Studies of Some Carbazole Derivatives via Cyclic Voltammetry and Convolution – deconvolution Transforms
Authors: Asiri Abdullah M. , Khan Salman A. , El-Hallag Ibrahim S. , Jnmes@polymtl.ca Ibrahim S.
Published: August 2018

Three carbazole chromophores derivatives featuring dicyno, cyano, ethyl acetate and dimethyl acetate groups as an acceptor moiety with a ? – conjugated spacer and N-methyl dibenzo[b]pyrole as donor were investigated electrochemically at a platinum electrode in 0.1 mol/L tetraethylammonium chloride (TEACl) in acetonitrile solvent via cyclic voltammetry, convolution – deconvolution transforms and digital simulation techniques. Cyclic voltammetric study revealed that the presence of a single reversible oxidative peak due to two sequential electron transfer (EE scheme) and unidirectional reductive peak which proceed as ECEC mechanism. The electrode reaction pathway, the relevant chemical and electrochemical parameters of the investigated carbazole chromophores were determined using cyclic voltammetry, convolution- deconvolution transforms and chronoamperograms. The extracted electrochemical parameters and the nature of the electrode reaction were verified & confirmed via digital simulation method.
Electrochemical Performance of Hollow α-Fe2O3 Spheres as Anode Material for Lithium-ion Battery
Authors: Du Zhijia , Zhang Shichao , Bai Zhiming , Jiang Tao , Liu Guanrao
Published: August 2018

α-Fe2O3 spheres were synthesized by a facile hydrothermal method followed by a calcination step. The crystalline structure and morphology of the synthesized materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The morphology of the sample consisted of porous hollow spheres that ranged about hundreds of nanometers and were composed of well crystallized nanoparticles about a dozen nm. The electrochemical properties of the sample were evaluated by cyclic voltammetry (CV) and charge/discharge measurements. The discharge/charge capacities in the first cycle achieved 1336/934 mAh g-1 at the rate of 0.2 C. The reversible capacity in the 50th cycle remained 840 mAh g-1 with impressive retention rate of 90%. This good lithium storage property was probably ascribed to the porous and hollow structure and nanoscale α-Fe2O3 particles, which enlarged the surface area and shortened the pathway for lithium ion migration. The appealing electrochemical capability indicated the potential implementation of hollow Fe2O3 spheres as anode material for future lithium-ion battery.
Hydrolysis Precipitation-assisted Solid-state Reaction to Li4Ti5O12 and its Electrochemical Properties
Authors: Xu Jie , Lv Chunju , Tian Guanglei
Published: August 2018

Spinel lithium titanate (Li4Ti5O12) materials were synthesized by a hydrolysis precipitation-assisted solid-state method in the temperature range from 600 to 900℃ for large-scale production. DSC/TGA, XRD and SEM were used to characterize the as-prepared samples. The optimum synthesis condition was examined in relation to the charge–discharge performance. It was found that when the dry hydrolysis precipitation precursor with 8% Li excess was calcined at 700–800℃ for 12 h in air, a pure Li4Ti5O12 phase was obtained. The as-obtained material has the best electrochemical performance due to its narrow size distribution and precise stoichiometry of the oxide.
Electrochemical performance of M3(BTC)2·12H2O (M=Co, Ni, and Zn) for Supercapacitors
Authors: Liao Chenmin , Zhao Jiachang , Tang Bohejin , Tang Aomin , Sun Yanhong , Xu Jingli
Published: August 2018

A series of Metal-Organic Frameworks (MOFs) based on 1,3,5-benzenetricarboxylic (BTC) acid and M(II) acetate hydrate (M=Co, Ni, and Zn) were successfully synthesized and named as M3(BTC)2·12H2O. These compounds were examined by X-ray diffraction (XRD) patterns. Electrochemical properties of the materials were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) in 6 M KOH aqueous solutions. The maximum specific capacitance of Ni3(BTC)2·12H2O is found to be 429 F g-1 at 5 mV s-1 and 154 F g-1 at 200 mV s-1 scan rate.
A Comparison of Exfoliation Methods on Microstructure and Electrochemical Performance of Graphene Nanosheets for Supercapacitors
Authors: Li Xinlu , Song Hongfang , Wang Hao , Li Hongyi , Zhang Yuxin , Huang Jiamu
Published: August 2018

Graphene nanosheets (GNS) were exfoliated by thermal expansion and microwave irradiation, respectively. The influence of exfoliation methods on GNS’s surface structure and electrochemical property were analyzed. The porosity structure of GNS was measured by N2 adsorption. The N2 adsorption results proved that both the specific surface area and pore volume of the GNS exfoliated by thermal expansion are larger than those by microwave irradiation. And the surface morphology was observed by scanning electron microscopy and transmission electron microscopy. The electrochemical performance of the graphene nanosheets were comparatively tested by cyclic voltammetry and galvanostatic discharge-charge tests. The GNS via thermal expansion exhibited better electrochemical property with the specific capacity of 188 F/g at the current density of 0.1 A/g.
Electrical Stress-directed Evolution of Biocatalysts Community Sampled from A Sodic-saline Soil for Microbial Fuel Cells
Authors: Sathish-Kumar K. , Solorza-Feria Omar , Vázquez-Huerta Gerardo , Luna-Arias J.P. , Poggi-Varaldo Héctor M.
Published: August 2018

Anode-respiring bacteria (ARB) perform an unusual form of respiration in which their electron acceptor is a solid anode. The focus of this study was to characterize the electrical stress direct evolution of biocatalysts as a way of enriching the community with ARB for microbial fuel cell. The original microbial consortium was sampled from a sodic-saline bottom soil (Texcoco Lake). Interestingly, iron (III) reducing bacteria consortium in the sodic-saline bottom soil was 8500 ± 15 MPN/100 mL by the most probable number method, since microbial reduction of iron (III) is reported to be associated to anode-respiring capabilities. Cyclic voltammetry studies of electrochemical stressed biofilm-ARB were conducted at 28th and 135th days, and an irreversible electron transfer reaction was found possibly related to electron transfer reaction of the cytochrome. The electrochemical impedance spectroscopy results revealed that the resistance of the biofilm-ARB decreased with time (28th day-11.11 ω and 135th day- 5.5 ω ), possibly associated to the adaptability of electroactive biofilm on the graphite electrode surface. Confocal microscopy showed that the biofilms are active in nature and the biofilm-ARB attained ~40 μ m thickness at the 136th day. Electrical stressed-ARB gave a maximum power density of 79.4mW/m2, and unstressed-ARB gave a maximum power density of 41.0mW/m2 in a single-chamber microbial fuel cell (SCMFC). All these electrochemical experiments and evaluation suggest that the electrical-stress directed evolution of ARB community was associated to a more efficient extracellular electron transfer process in SCMFC.
Catalytic Activity of Porous Pd-Ni Thin Foam towards Electrooxidation of Methanol
Authors: Jin Ming , Ma Houyi
Published: August 2018

Porous Pd-Ni thin foam was fabricated by a rapid one-step electrodeposition process within hydrogen bubble dynamic template and characterized by SEM, EDS, and cyclic voltammetry. Morphology and composition of the foam can be modified significantly by applying different deposition conditions, such as concentration ratio of Pd (II) ions to Ni (II) ions in electrolytic solution and deposition time. Electrocatalytic activities of the foam towards methanol oxidation in alkaline media were investigated, which depend mainly on Pd components and its morphology. Low nickel content can assist Pd further enhance the electrocatalytic performance, particularly the tolerance to intermediates of methanol oxidation, while high nickel content brings adverse effect. The high catalytic activity and the low cost of the Pd-Ni foams enable them to be promising electrocatalysts for the oxidation of methanol in alkaline media.
Novel Ru(II) Heteroleptic Complexes Anchored to TiO2 Nanocrystalline: Synthesis, Characterization and Application to Dye-sensitized Solar Cells
Authors: Shahroosvand Hashem , Nasouti Fahimeh
Published: August 2018

A series of heteroleptic ruthenium(II) complexes from Ru(NO)(NO3)3 as precursor have been designed, synthesized, and characterized by 1H-NMR, FT-IR, UV–Vis, PL, ICP and CHN analyses. The reaction details and features were described in detail. Solar cells involving thin films of anatase TiO2 impregnated with these dyes were prepared using an electrolyte solution of I-/I3- in acetonitrile as the electron mediator, and their photovoltaic performance was evaluated. The system lacking carboxyl moiety as anchoring groups shows poor photovoltaic performance. We found that the efficiency of cell is strongly affected by the presence of carboxyl groups of the sensitizing dye, the efficiency of 1,2,4,5-benzentetracarboxylic acid(btec) ruthenium(II) (with three btec moieties) adsorbed on nanocrystalline TiO2 films being 4 times as large as that of bahtophenathrolin ruthenium(II) (with one nitrato group) adsorbed on the same films . An incident photon-to-current conversion efficiency (IPCE) of 8% at 510 nm was obtained for tris(1,2,4,5-benzentetracarboxylic acid) ruthenium(II) (4)
Selective Determination of Iron(III) in Sea Water by Gold Nanoparticles Self-assembled with N-carboxyl- L-cysteine
Authors: Liu Benzhi , Wang Min
Published: August 2018

Application of gold nanoparticles self-assembled with N-carboxyl- L-cysteine for the determination of iron(III) was investigated. Differential pulse adsorptive stripping voltammetry was used to detect iron(III). Various operational parameters were investigated and discussed in terms of their effects on the measurement signals. A linear range from 0.1 nM to 1.8 nM with a detection limit of 0.03 nMwas obtained under optimized conditions. The applicability of the method was successfully tested by determination of iron(III) in sea water samples.
Effect of Dye on the Performance of Nitrogen Doped TiO2 Solar Cell Prepared via Ammonia Treated Liquid Phase Deposition Technique
Authors: Rahman M. Y.A. , Umar A. A. , Saad S. K.M. , Salleh M. M. , Ishaq A.
Published: August 2018

This paper reports the utilization of nitrogen-doped TiO2 nanoparticle in dye-sensitized solar cell (DSSC). The TiO2 nanoparticles were synthesized on ITO substrate via a simple technique, namely, liquid phase deposition (LPD). 7.5% nitrogen from NH3 dopant source was doped into the TiO2 samples by spin coating technique. The nitrogen doped TiO2 samples were then utilized as photovoltaic materials in a photoelectrochemical cell of ITO/TiO2/electrolyte/platinum sensitized with N-719, N-3 and Z-907 dyes, respectively. It was found that the photovoltaic parameters such as short-circuit current density (Jsc), open-circuit voltage (Voc), fill factor (FF) and power conversion efficiency (η) are influenced by the organic dyes. The cell sensitized with N-719 dye demonstrated the highest photovoltaic parameters. These results are supported with the UV-Vis analysis, showing that the N-719 dye possessed the broadest window absorption and the highest absorption peak in visible region of light spectrum.
Enhanced Catalytic Activity for the Ethanol Oxidation Reaction (EOR) using Novel Pt-Fe3O4/MWCNT Bimetallic Electrocatalyst
Authors: González P. C. Meléndez , Montemayor Sagrario M. , Acosta D. Morales , Verde-Gómez Y. , Escobar B. , Varela F. J. Rodríguez
Published: August 2018

In this work, 20% Pt-Fe3O4/MWCNT (Pt:Fe3O4 weight ratio of 80:20) and 20% Pt/MWCNT nanoparticles were synthesized and characterized as anode electrocatalysts in H2SO4 media. First, the electrocatalyst were submitted to accelerated catalyst degradation test (ACDT) by performing 500 cycles between 0.6 and 1.2 V (vs. SHE). Then, their performance for the EOR was evaluated. The magnetite-containing nanoparticles demonstrated to be highly electrochemically stable, with negligible surface area losses (less than 7%) in thehydrogen adsorption/desorption region. Moreover, Pt-Fe3O4/MWCNT showed a significantly enhanced catalytic activity for the EOR when compared to Pt/MWCNT, with almost 46% increase in current density when using Fe3O4 as co-catalysts.
Impedance Analysis of Growth and Morphology of Electropolymerized Polypyrrole Nanocomposites
Authors: Torabi Morteza , Soltani M. , Sadrnezhaad S. K.
Published: August 2018

Pure polypyrrole (PPy), PPy/Al2O3 and PPy/SiO2 nanocomposites synthesized galvanostatically using different polymerization charges. Electrochemical impedance measurements of pure polypyrrole revealed that the film thickness affected the impedance responses. The characteristic frequencies vs. film thickness that obtained using Cole-Cole plots showed that electrodeposition mechanism changed from 3D to 1D after nuclei overlapping for pure PPy. Analysis of the nanocomposites impedance spectrums revealed no changes during the film growth, i.e. deposition continues 3D even after nuclei overlapping. Scanning electron microscopy (SEM) confirmed the impedance results and showed that the morphology of the thick pure PPy film is 1D, while the deposition of the nanocomposites was 3D with compact and very fine structure.
Structural, Thermal and Electrical Conduction Studies on LiNiPO4: RE (RE= La, Nd) Prepared by Polyol Method
Authors: Karthickprabhu S. , Hirankumar G. , Thanikaikarasan S. , Sebastian P. J.
Published: August 2018

LiNiPO4 and LiNiPO4: xRE (RE = La, Nd) (x = 0.01 mol%, 0.03 mol%, 0.05 mol%, 0.07 mol%, 0.09 mol%) samples have been prepared by polyol method using 1, 2 propanediol as a polyol medium. XRD patterns have indicated that the pristine LiNiPO4 is well crystallized with orthorhombic structure pnma space group and structurally stable compound upon doping of rare earth metals. Functional group analyses have been carried out by FTIR spectroscopic analysis. TG analysis shows that no weight loss has been observed above 600°C for both Nd3+ and La3+ doped LiNiPO4. The morphology of the samples was analyzed through Scanning Electron Microscopy. The conductivity of LiNiPO4 was found to be improved by 2 orders by doping of rare earth ions. It is found that lanthanum is an excellent dopant for LiNiPO4 than neodymium due to the formation of free ion sites which causes the enhancement of conductivity. Dielectric studies support that doping of La3+ is favorable for conduction compared with Nd3+ doping.
Synthesis, Characterization and Electrochemical Properties of Schiff Base Complexes Derived from Amino Acids
Authors: Suja Pon Mini P. S. , Antony R. , Manickam S. Theodore David , Thanikaikarasan S. , Subramanian R. , Balakumar S. , Mahalingam T. , Saldana Sergio , Ixtlilco Luis
Published: August 2018

A new Schiff base, derived from isatin and an amino acid, aspartic acid, and its complex with Zinc(II) were synthesized. The formation of Schiff base and its Zn(II) complex were characterized and confirmed by elemental (C,H and N) analysis; molar conductance, magnetic measurements; and FT-IR and UV-VIS spectroscopic methods. From the electronic spectral and molar conductance data, four - coordinated tetrahedral geometry was assigned to the synthesized complex. In addition, the redox behavior of the complex was investigated using cyclic voltammetry technique. The redox properties were scrutinized with nitrogen as well as aerobic atmospheres. The redox process was measured to follow one electron reversible mechanism. The electrochemical properties of the complex have not been affected by the atmospheric conditions due to the non-reactivity of the complex with atmospheric gases like CO2 and O2.
Determination of Lead (Pb2+) by Anodic Stripping Voltammetry Based on [Ru(NH3)6]3+/Nafion Modified Electrodes
Authors: Palisoc Shirley Tiong , Natividad Michelle Tiamzon , DeVera Patricia Denise , Tuason Benjamin Simone B.
Published: August 2018

Chemically modified [Ru(NH3)6]3+ doped Nafion® thin film was fabricated on indium tin oxide (ITO) coated glass electrodes by using the drop-coating method to detect heavy metal ions of Pb(II) in de-ionized water analyte solution via anodic stripping voltammetry (ASV). This study also determined the effect of varying the concentration of the mediator ([Ru(NH3)6]3+) on the detection of the said heavy metals. The redox mediator Ru(NH3)6]3+ used in the study was effectively incorporated and immobilized within the Nafion modified electrodes. Lead concentration in the electrolyte solution and the concentration of the redox mediator was varied to control the properties of the fabricated electrodes which utilized for heavy metal detection through ASV. The conducting properties of ITO electrodes were enhanced with the deposition of Nafion® attaining minimal interference. The stripping current peaks increased with the concentration of the heavy metal present in the solution as well as with the mediator concentration.
Capacitance Properties of Electrodeposited Polyaniline Films on Stainless Steel Substrate
Authors: Al-Owais A. A. , El-Hallag I. S. , Ghanem M. A. , El-Mossalamy E. H.
Published: August 2018

Polyaniline (PANI) thin films were successfully synthesized from a mixed solution of 1M aniline and two different concentration solutions of H2SO4 on a stainless steel substrate. The capacitance properties of polyaniline (PANI) films, have been determined and examined in the selected media of two different concentrations of H2SO4 acid using cyclic volammetry technique. Cyclic voltammetric measurements have shown that PANI films grown by cycling the potential between -0.2V and 1 V in 1M H2SO4 and 2M H2SO4 on SS electrode. The electrochemical characterization of the electrode was carried out by means of cyclic voltammetry. The results show that polyaniline has a high specific capacitance of 702.1 F.g-1 and 810.5 F.g-1 at 10 mV s-1 in 1M H2SO4 and 2M H2SO4 respectively. This indicates that the promising feasibility of the polyaniline used as an electrochemical capacitor material in the sulphuric acid solutions.
Spin Coated Hexaammineruthenium(III)/Nafion/ITO electrodes for the Determination of Lead(II) and Cadmium(II) via Anodic Stripping Voltammetry
Authors: Palisoc Shirley T. , Kaw Kevin Anthony Y. , Natividad Michelle T. , Robles Julita C.
Published: August 2018

Hexaammineruthenium (III) [Ru(NH3)6]3+-Nafion®-isopropanol diluted films were spin coated on indium tin oxide (ITO)-coated glass substrates. The fabricated samples were used to determine the presence of lead and cadmium in solution using anodic strip-ping voltammetry (ASV). The calibration sensitivity of the electrodes for lead and cadmium were approximately equal. Detection limits of 5ppb and 4ppb were determined for lead and cadmium respectively. Real sampling tests with commercially available yellow water color yielded 0.7106 ppm of Pb with ASV. The result was verified with atomic absorption spectrometry (AAS) which yielded 0.6923ppm of Pb.