bluuebunny/crossref_metadata_2025 huggingface dataset:
Electrospun PVDF/PMMA/SiO2 Membrane Separators for Rechargeable Lithium-Ion Batteries
Authors: Wu Xiao Lin , Lin Jie , Wang Jian Yan , Guo Hang
Published: May 2015

In this paper composite nanofiber membranes were prepared by electrospinning technology from poly (vinylidene fluoride) (PVDF)-poly (methyl methacrylate) (PMMA)-SiO2blend solutions with different PMMA and SiO2contents. It was found that the diameter of electrospun nanofibers was greatly increased with the added PMMA content but decreased with the added SiO2content, and when both PMMA and SiO2were added the diameter of electrospun nanofibers was decreased. With a proper ratio of the PMMA and SiO2added, the electrospum nanofiber membrane could have a suitable diameter with high porosity. The XRD results revealed that electrospun nanofiber membranes contained mainly β-phase crystal structure of PVDF, and its crystalline is reduced with the added PMMA and SiO2contents due to the inhibited crystallization of the polymer by the inorganic particles and PMMA during the solidification process. These nanofiber membranes exhibited a high electrolyte uptake, around 300%. Moreover, the incorporation of PMMA and SiO2into the nanofiber membrane improved the ionic conductivity from 1.7×10−3S/cm to 2.0×10−3S/cm at room temperature. Compared with commercial film PE, their cell cycle and charge and discharge performance were also greatly improved.
Corrosion Behavior of SAMs Modified Silver-Coated 316LSS as PEMFC Bipolar Plates
Authors: Yan Xiao Jun , Zhuang Jian Bo , Huang Nai Bao , Liang Cheng Hao , Wang Hong Tao , Xu Li Shuang
Published: May 2015

In order to improve the anti-corrosion characteristic of Ag-coated 316SS bipolar plates in PEMFC environment, self-assembled monolayer (SAM) was prepared on its surface by chemical methods. The electrochemical characteristic of modified bipolar plate was also investigated. The results indicated that the SAM was composed of dodecyl thioalcohol. After forming SAM, the bipolar plate’s contact angle increased from 58° to 102°. In addition, its double layer capacitance (Cd) was decreased and charge transfer resistance was increased. The homogeneous SAM, which acted as a protective barrier, inhibited the corrosive ion from corroding. SAM may provide significant protection against corrosion in PEMFC environment.
Pretreatment with Huperzine A-Loaded Poly(lactide-co-glycolide) Nanoparticles Protects against Lethal Effects of Soman-Induced in Mice
Authors: Zhang Rui Hua , Li Li Qin , Wang Chen , Lu Xiao Jing , Shi Tong , Xu Jian Fu , Song Liang Cai , Wang Hui Fang
Published: May 2015

Huperzine A (HupA), an alkaloid isolated from theChinese club moss, is a reversible inhibitor of cholinesterases which cross the blood-brain barrier and show high specificity for acetylcholinesterase (AChE). However, HupA induces unwanted side effects in an effective dose against nerve agent poisoning. In the present study, HupA–loaded poly (lactide-co-glycolide) nanoparticles (HupA-PLGA-NP) were prepared using the O/W emulsion solvent evaporation method. The results of SEM demonstrated that HupA-PLGA-NP had an spherical shape and a smooth surface without pores. It’s mean diameter and PDI were 208.5±3.6nm and 0.09±0.01 respectively. The Zeta potential was-35.3±1.8mV and the drug loading was 2.86±0.6%.In vitrodrug release studies showed that HupA-PLGA-NP had a sustained-release behavior in phosphate buffer solution, The accumulated amount of HupA was about 72.1% at 48h with a low burst release within 30min. The LD50values of HupA and HupA-PLGA-NP were 1.40 and 4.85mg/kg respectively, showing that the toxicity of HupA was reduced by 3.5 times. We evaluated the protective efficacy for different doses of HupA or HupA-PLGA-NP against 1.0×LD95(143.0μg/kg) soman toxicity. The results confirmed that HupA (0.3~0.5mg/kg) or HupA-PLGA-NP (0.5~1.5mg/kg) could ensure animals survive. However, about 10% of the animals injected with HupA (0.8mg/kg) died, while no animals died when injected with HupA-PLGA-NP (1.5mg/kg). Aim to 100% survival rate, the effective protective time (12h) of HupA-PLGA-NP (0.5mg/kg,iv) against 1.0×LD95soman toxicity in mice was significantly prolonged compared with that of HupA (4h). The study of AChE activity showed that whole-blood and supernatant of brain diluted by 80-fold and 10-fold respectively were optimum in this study. AChE inhibition after administration of HupA and HupA-PLGA-NP (0.5mg/kg,iv) was recorded and analyzed, The peak values of AChE inhibition in whole-blood and brain by HupA-PLGA-NP (17.6% and 21.8%) were lower than those by HupA (33.7% and 31.9%) and AChE inhibition time by HupA-PLGA-NP was longer than that by HupA. These data confirmed that HupA-PLGA-NP had less toxic and more longer time than HupA against 1.0×LD95soman poisoning and warrant further development as a potent medical countermeasure against chemical warfare nerve agents (CWNAs) poisoning.
Sintering Behavior and Electrical Property of Surface Treated Silver Nanoparticle for Electronic Application
Authors: Xie Hui , Xiong Na Na , Zhao Yu Zhen , Wang Yue Hui
Published: May 2015

Large-scale silver nanoparticles with fine dispersion and narrow size distribution were synthesized by reducing silver nitrate with sodium borohydride and sodium citrate and using poly (vinylpyrrolidone) as an adsorption agent in the ethanol solution. The sintering behavior and electrical properties of silver nanoparticles treated with and without glutaric acid were studied. Morphology studies showed that the treated silver nanoparticles obviously agglomerated and began to sinter at 200 °C and the sintering temperature is higher at least 50 degrees than that of the untreated silver nanoparticles The treated silver nanoparticles as fillers of electronically conductive adhesives (ECAs) is more advantageous to the increase of the conductivity. Otherwise, only in the conditions of the appropriate sintering temperature and loading of silver nanoparticles, the high conductivity of the ECAs was obtained. The effect of the treated silver nanoparticles on the electrical properties contributes to the surface activation and sintering behavior.Keywords: Silver nanoparticle, Sintering Behavior, Surface treatment, Electrical property
Fabrication and Thermal Performance of Copper Pillars Modified Micro Heat Pipe (MHP)
Authors: Zou Liang Liang , Luo Yi , Liu Ji Guang , Yu Bei Ke , Shan Qing , Wang Xiao Dong
Published: May 2015

With the excellent thermal conductivity and the compatibility to micro electromechanical systems technology, silicon is widely used in micro heat pipes (MHPs). Copper shows higher heat transfer capability and capillary traction than silicon. Copper pillars modified microgrooves were fabricated on the silicon wafer using electroforming technique in this paper. Water contact angle measurements and thermal behavior tests were employed to the fabricated microgrooves and MHPs. Under the input power of 4 W, how the working fluid flowed in the microgrooves and steam chamber was easily observed by digital camera. The experiments demonstrated the working fluid flowed via copper pillars instead of the silicon microgrooves due to the adhesive force between working fluid and copper pillars were larger than that between working fluid and silicon microgrooves. This work showed copper pillars had a better capillary traction than the silicon microgrooves, and could make the MHP work as a vapor chamber.
Study of PSG Thickness Uniformity Influencing Factors in LPCVD
Authors: Lü Wen Long , Zhan Zhan , Du Xiao Hui , Zhou Ru Hai , Zhang Hao Er , Wang Ling Yun , Sun Dao Heng
Published: May 2015

In the fabrication of SiC high-temperature sensors, the phosphosilicate glass film (PSG) is deposited on the SiC wafer as the intermediate layer, achieving the bonding of two SiC wafers. The ease of bonding is affected by the PSG film thickness uniformity. In this paper, the flow field distribution in the LPCVD tube is simulated under different deposition conditions,obtaining the wafer surface uniformity of gas flow distribution, which was verified by the experiment, The aim of this work is to study the impact of several deposition conditions such as the location of SiC wafers, wafer inclination and wafer spacing on the thickness uniformity of PSG film. Experimental results show that SiC wafer position in the tube and its own inclination and wafer spacing affect gas flow field on the SiC wafer surface,leading to uneven distribution of gas flow, thus affect the thickness uniformity of PSG.
High-Efficiency Preparation of N-Doped Titania with High Visible Light Photocatalytic Activity Using Composite N Precursor
Authors: Hu Yu Long , Zhang Xiao Dong , Liu Hong Fang , Guo Xing Peng
Published: May 2015

N-doped TiO2 nanoparticle powders were prepared efficiently by the sol-gel method using triethylamine and ammonium hydroxide as composite N precursor. The as-prepared N-doped TiO2 precursor powders were calcined at 300°C in air for 3 h and subsequently annealed at 300°C in air for 2.5 h. The samples were characterized by X-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, thermo-gravimetric analysis, and X-ray photoelectron spectroscopy. The visible light photocatalytic activities of as-prepared samples were evaluated by photodecomposition of methyl orange (MO). The results show that the as-prepared samples have high visible light photocatalytic activities. Triethylamine produces the N-species doped in TiO2 lattice responsible for the high visible light photocatalytic activity. Ammonium hydroxide makes the gel of the TiO2 nanoparticles nitrided by triethylamine gelate further and facilitates significantly the centrifugation of the gel. An annealing treatment can eliminate effectively the outer N species caused by ammonium hydroxide and the surface organic residues, improve effectively crystallinity, and retain the N species caused by triethylamine.
Study on Mechanism of Phase Forming in Ni+ Implantation into Ti6Al4V at Elevated Temperature
Authors: Wang Yuan , Yu Xiao Hua , Yang Hai Long
Published: May 2015

Recently, due to the prediction of the forming phase only focuses on the case which a simple metal ion implants into a single metal matrix, we will study that a simple metal ion is implanted into alloy matrix in this paper. The forming phases in Ni+implantation into Ti6Al4V at elevated temperature will be predicted by the effective heat of formation (EHF) model. The results show that the prediction is consistent with the experimental findings, the first-phase is TiNi with the most negative EHF, the second-phase is Ti2Ni which component concentrations of Ni limited element is lower and locates on the left in the Ti-Ni binary alloy phase diagram, and the TiNi3phase is not found in the experiment. Simultaneously, we explain correctly why the Ni-Al or Ni-V phases don’t generate in Ni+implantation into Ti6Al4V at elevated temperature.
Performance Investigation of TiO2 Nanofluid Coolant for Automobile Cooling Applications
Authors: Chen Jin Mao , Sun Xiao Ying , Leng Guan Jun , Feng Jing Heng
Published: May 2015

This study focused on the evaluation of TiO2 nanofluid coolant for automobile engine cooling applications. It was observed that, about 3% of thermal conductivity enhancement and above 10% convective heat transfer enhancement could be achieved with the usage of 1.0 wt.% TiO2 nanofluid coolant compared to base coolant without nanoparticles. More importantly, corrosion-inhibiting properties of TiO2 nanofluid coolant were investigated, which indicated that the nanofluid coolant possess the characteristics of a qualified engine coolant should have. The evaluation results showed that the nanofluid coolant could be a promising engine coolant for automobiles.
The Simulation and Experimental Analysis of Hydrodynamic Focusing Effect inside a Rectangular Microchannel
Authors: Feng Shuai Jie , Shi Xin Qun , Zeng Jing , Peng Yan , Liu Mei
Published: May 2015

This paper models the hydrodynamic focusing performance of a micro-fluidic chip with rectangular cross-sections, and the relationships between the aspect ratio, flow rate ratio of sheath flows to the sample flow, and dimensions and position of the focused sample flow are obtained. The simulation results are consistent with theoretical outcomes. And preliminary experiments were carried out to prove the simulation results.
TCAD Study of the Raised SiGe Source/Drain in 40nm PMOS
Authors: Zhong Min , Zhao Yu Hang , Chen Shou Mian , Li Ming , Zeng Shao Hai , Zhang Wei
Published: May 2015

An embedded SiGe layer was applied in the source/drain areas (S/D) of a field-effect transistor to boost the performance in the p channels. Raised SiGe S/D plays a critical role in strain engineering. In this study, the relationship between the SiGe overfilling and the enhancement of channel stress was investigated. Systematic technology computer aided design (TCAD) simulations of the SiGe overfill height in a 40 nm PMOS were performed. The simulation results indicate that a moderate SiGe overfilling induces the highest stress in the channel. Corresponding epitaxial growth experiments were done and the obtained experimental data was in good agreement with the simulation results. The effect of the SiGe overfilling is briefly discussed. The results and conclusions presented within this paper might serve as useful references for the optimization of the embedded SiGe stressor for 40 nm logic technology node and beyond.
Experimental Study on Velocity of Flyer Based on Silicon
Authors: Fu Qiu Bo , Wang Yao , Wang Meng , Qin Wen Zhi , Guo Fei
Published: May 2015

This paper researches the characteristic to the flyer velocity of silicon flyer. The material of flyer is different in comparison to polyimide which is considerde to conditional flyer. It is found that the movement trendency is clearly different of velocity between silicon flyer and polymide flyer, which is resulted by modality change. The silicon flyer velocity decreases gradually with the increase of flyer thickness. The inclusion is also applicable for polyimide flyer. It is clearly that the fatal influence parameter is silicon flyer thickness for slapper detonator based on MEMS fabrication process, which determined the success of explosion.
A New Method of Design and Verification of Digital Silicon Gyroscopes Closed-Loop Driving System Based on MicroBlaze
Authors: Sun Peng , Shao Qi , Liu Ying Yu , Chen Wei Ping
Published: May 2015

The article brings out a digital silicon gyroscopes closed-loop driving system using the phase relationship of the input driving signal and the signal of the forced motion of the mass block in sensor structure based on analyzing the working principle and phase characters of digital silicon gyroscopes. We make a low-cost, simple and high precision measurement technique for resonant frequency of silicon micro-machinery gyroscopes by the whole digital locked loop system designed with MicroBlaze method. Dichotomy and Fourier transform spectrometry method constitute the algorithm of the system and the solution precision can be determined by the number of the times of approximation. Under the control of the MicroBlaze softcore, the system realizes the realization of the digital signal, the high speed frequency transformation, the acquisition of mass block response signal and the calculation of phase difference. Lastly, each module of the system and the whole system are simulated, the whole system is approved on the test broad.
Study on Magnetization and Detection the Metal Particle in Harmonic Magnetic Field
Authors: Zhang Xing Ming , Zhang Hong Peng , Bo Zhao , Chen Hai Quan , Sun Yu Qing
Published: May 2015

Inductance detection methods of metal particle in hydraulic oil are generally based on the inductance change detection. With this method, when particles pass through the microchannel, ferromagnetic and non-ferromagnetic metal particle can be distinguished by monitoring inductance. In this study, it was found that not only inductance pulse but also resistance pulse was produced when detecting particle by inductance detection method. The theory of inductance or resistance change caused by particle is presented from the perspective of electromagnetism in this paper. To verify this phenomenon, the oil sample mixed with different metal particles was forced through the detection coil of microfluidic by constant flow rate. Then several sizes of iron and copper particles were measured. Experimental results showed that the resistance pulses caused by iron particles and copper particles were positive. And for copper particle, SNR (Signal Noise Ratio) of copper particles detected in improved effectively by detecting the resistance pulse.
Design of Minimal Capacitance Detect Circuit for MEMS Capacitive Sensor
Authors: Qu Hao , Yu Hui Jun , Zhou Wu , He Xiao Ping , Du Lian Ming , Peng Bei
Published: May 2015

The capacitance among the structure of the accelerometer is rather small, usually at sub-pF level. Detection of the capacitance among the sensor’s tiny structure and analysis of the variation of these capacitances are necessary to improve the sensor’s performance. In this paper, one capacitance detect circuit for minimal capacitance is designed. Simulation and experiment results indicate a good linearity when the circuit is applied to detect capacitance range from 0.5pF to 5pF.
A New Design of a Piezoelectric Triaxial Micro-Accelerometer
Authors: Wang Jian Yan , Wang Ting Ting , Guo Hang
Published: May 2015

Accelerometer in MEMS always is made by capacitive or piezoresistive, whose dynamic response is not good, the operating frequency is narrow, and the cross-axis sensitivity is low. A new type of piezoelectric micro-accelerometer is designed, and its structure is “x” type. The sensing unit is piezoelectric PZT films, which is achieved by sol-gel method. The accelerometer is a triaxial accelerometer. The theoretical and simulation analysis is used to achieve the charge sensitivity and response frequency, and also get the optimal structural parameters. A new circuit connection is proposed to improve the sensitivity and avoid the cross-axis sensitivity. The design achieves the z-axis sensitivity with more than 40 pC/g, x, y-axis sensitivity with more than 8pC/g, and the response frequency is about 3000Hz.
The Test and Simulation Modeling of Micro Scale Solid Particles Fuel Cloud Dispersal under High Dynamic
Authors: Jin Xin , Lou Wen Zhong , Guo Ming Ru , Dai Xi Ming
Published: May 2015

Cloud forming by solid explosive dispersal plays a decisive factor for twice-detonating FAE. The study of the flow field of internal cloud field can be more intuitive to understand the whole process of the formation of cloud diffusion, and it also has an important role to the delay time setting of secondary detonating fuze. Internal parameters of spreading cloud are difficult to obtain even through by the experiment method, but numerical analysis and simulations method can get the parameter. In this paper, we use experimental and simulation methods to study fuel dispersal process, aims to establish an effective and reliable mathematical models of cloud dispersal, and get the model data coinciding with the real situation.
The Influence of Modifying HDPE on Properties of the Surface
Authors: Dulebová Ľudmila , Garbacz Tomasz , Krasinskyi Volodymyr , Duleba Branislav
Published: May 2015

The aim of the paper was to discover the influence of modifying HDPE with selected agents that is a blowing agent, in the course of the extrusion process, inclusive of determination how the modification affects selected physical properties and properties of the surface of HDPE extrusion product. Endothermic chemical blowing agents in the amount of 0.6 % by mass were used in the research. The article presents selected results of examination of melt flow rate (MFR) and microscopic structure.
The Causes of Corrosion Formation of Packaging Sheets after Plastic Deformation
Authors: Spišák Emil , Majerníková Janka , Spišáková Emília
Published: May 2015

The tinplate possesses several important advantages, such as drawability, good solderability and corrosion resistance. Plastic and strength properties are better because recrystallization annealing is including in the sheet production process. Some products may be either continuously annealed (CA) or batch annealed (BA). In the contribution we deal with relation between magnitude of plastic deformation and of its influence to corrosion resistance of tinplates.
Release of Metals from Cans during Short-Term Storage
Authors: Halama Maroš , Beyreder Thomas , Vasilková Daniela , Halamová Dáša
Published: May 2015

Nowadays, cans are used widely to store and keep safely juices, drinks and liquid products with different taste. Especially in food industry one has to consider the eﬀects of the content of inner side of the can due to the fact that some of the liquids can be very aggressive to the metals and surface treatment. The subject of this paper was to investigate the run-oﬀ-eﬀect of metals from can into the solutions and analyze the data retrieved by Electrochemical Impedance Spectroscopy (EIS) and Linear Voltammetry (LV) techniques. We have observed phenomenon that release of metals is not only time but also temperature dependent. We have built equivalent circuits models for various conditions for both aluminum and tin cans. The aim of the project was to calculate “run-off” effect of Al and Sn from cans into drink during short-term storage and compare it with WHO norm.
Electrochemical Characteristics of Anodized Ti-6Al-4V Alloy
Authors: Ivašková Martina , Lovíšek Martin , Miková Katarína
Published: May 2015

Titanium and its alloys are still popular in different kind of industry. Ti-6Al-4V alloy is usually used due to its two-phased composition, which cause good mechanical properties. Corrosion resistance of this material can be improved by anodic oxidation. This electrochemical method is used to increase the thickness of titanium dioxide. The aim of the research was color anodizing of the Ti-6Al-4V alloy in the 7% H2SO4 acid solution at 20 ± 0.5°C and for 30 seconds at different voltages (15-90V). The electrochemical characteristics were determined by potentiodynamic tests in the 0.1M NaCl solution. The obtained results were analyzed by the Tafel-extrapolation method. Finally, the corrosion current densities and corrosion rates were evaluated. In fact, the corrosion rates of anodized alloys were 6 to 85 times lower against to ground surface.
Activity of Bacteria and Moulds on Surfaces of Commercial Wooden Composites
Authors: Vidholdová Zuzana , Iždinský Ján , Reinprecht Ladislav , Krokošová Jana
Published: May 2015

Bacteria and mould exposures are reported to be associated with allergies, respiratory symptoms and asthma. Wood products with antimicrobial surface would reduce the risk of spreading microbial infections especially in healthcare facilities and public buildings. In future is perspective of their use.In this study, twenty five wooden composites commercially produced in Slovakia having different surfaces were tested both against moulds – microscopic fungiAspergillus nigerandPenicilliumspp., and also against bacteriaEscherichia coliandStaphylococcus aureus. These organisms are commonly applied as test microbes in laboratory experiments. On the basis of bacteria and mould’s growth on the surfaces of used wooden composites, the tested surfaces have been divided to three groups: (1) wooden composites with high resistant surface, (2) wooden composites with medium resistance surface, (3) and wooden composites with not resistant surface.
Analysis of the Delamination in Drilling of Particle Board
Authors: Szwajka Krzysztof
Published: May 2015

Drilling is the most commonly used machining process in furniture industries. In this study the eighteen tests of tool durability for different values of the analyzed cutting parameters were carried out. Based on the results of investigations, the influence of selected parameters on the cutting surface quality was determined. Mathematical models based on analysis of variance (ANOVA), allowing to estimate the surface quality in the cutting process were proposed.
Testing of PVD Hard Coatings Applied to Coining Dies
Authors: Jakubéczyová Dagmar , Kalincová Daniela , Kaštan Rudolf
Published: May 2015

The requirements on tools used in the production of coins include high quality and reliability, dependent on the materials from which they are made, on manufacturing technology, heat treatment and final operations achieving functional area modification. Properties of the material of coins vary during their production and there is the so-called operational degradation that can be caused by an inappropriate technology of manufacturing. The quality of coining dies is expressed as their service life which ranges from approximately one hundred thousand to one million pieces of coins produced. Therefore, it is necessary to pay enough attention to the service life of coining dies. Surface treatment in the form of the application of hard PVD coatings is one of the ways of increasing the durability of coining die.In the present study, we analysed and tested three types of coatings deposited onto coining dies made of tool steel.
Modification of Milling Tools and their Coating for Machining Sandwich Materials
Authors: Kroupa Tomas , Bakša Tomáš , Hanzl Pavel , Zetek Miroslav
Published: May 2015

This article deals with special kind of machining of multi-layer laminar composites called sandwich composites. This material consists of two outer layers that overlap core material at the centre made from a light material. This material is used in the automotive industry in interior parts such as dashboards, decorative parts and panels. The product is folded from thin plastic and aluminum. As customers require high-end quality for higher class-vehicles, machining must be ensured at as high a level as possible to suit customer demands. Appropriate processing methods have been investigated experimentally in order to choose the best tool that would guarantee a consistently high quality of cut depending on high durability. Therefore it is still necessary to permanently test new tools with different types of coating, including thin films and different geometry to achieve the required quality at less clamping milling tools, which need to be changed after some pieces and edge sharpen.
Analysis of Short Glass Fiber Orientation in Injection Moulded Components
Authors: Duleba Branislav , Greškovič František , Sikora Janusz , Dulebová Ľudmila
Published: May 2015

Fiber reinforced polymer composites are common materials used to produce parts for structural applications. The attractiveness of these materials is a result of the combined advantages of the fiber reinforcing effect and the high production rates achievable by technologies such as injection molding. The fiber orientation in short fiber reinforced thermoplastics depends on injection moulding technology parameters. The aim of this paper is to propose possibilities for comparing fiber orientation of the real sample and the result from simulation software.
Surface Finish Techniques for FDM Parts
Authors: Gajdoš Ivan , Spišák Emil , Kaščák Luboš , Krasinskyi Volodymyr
Published: May 2015

Additive manufacturing technologies decrease production time and costs in engineering industry but also in other industries. Parts produced with Fused Deposition Modeling (FDM) have typical low surface finish quality. This paper is aimed on research of surface finishing technologies applicable to improve the quality of FDM prototypes surface finish. Pretreated samples were blasted with sodium bicarbonate and glass beads. The values of Raand Rzwere measured on the samples and compared the impact of selected pre-treatment, blasting medium and blasting conditions on surface finish quality of FDM prototypes.
The Surface Treatment Influence on the Occurrence of the Critical State Relating to the Needle as the Operating Tool
Authors: Pešlová Františka , Pavúčková Adriána , Ďurovcová Michaela , Hajdúchová Luba , Janeková Mariana , Koštialiková Daniela , Krum Stanislav
Published: May 2015

The research work deals with the evaluation of limit states of machine needles failure where significant operational wear was anticipated. It focuses on the description of limit states, their causes and subsequent brittle fracture as a result of degradation. The experiment dealt with an evaluation of prepared microstructures followed by the fractography observation. Due to the fact that chemical composition of the material was not originally determined distribution of the chemical elements by linear and area method was performed within the experimental part. The work confirmed incorrect selection of the base material that although coated was typical by rapid degradation and failure which resulted in economic losses.
Short-Term Corrosion Protection of Materials Using Nanocoatings
Authors: Pavelková Daniela , Koldová Lenka , Podjuklová Jitka , Siostrzonek René , Pěnička Zdeněk , Menshikov Vladimír
Published: May 2015

The preservation ability of coatings applied to the materials of steel products, steel structures, etc., for short-term corrosion protection is a very delicate and modern theme. In cooperation with the project Pre-seed, we can pay closer attention to activities involved with this topic. The project Pre-seed at the Technical University of Ostrava, which is part of the Operational Programme of Research and Development for Innovation, attempts to support the preparation of the commercialization of promising technologies and inventions with high application potential that were developed at the Technical University of Ostrava. This paper focuses on the short-term corrosion protection of steel products, steel structures, and engineering products using thin nanocoatings. This experimental work is primarily concerned with the production and development of samples that demonstrate the innovativeness and functionality of the issue. Furthermore, the project addresses important factors affecting the quality and durability of the coating system. The results of the experimental part show us some very interesting outputs that need to be further studied and developed.
Drop-Landing Performance and Knee-Extension Strength After Anterior Cruciate Ligament Reconstruction
Authors: Kuenze Christopher M. , Foot Nathaniel , Saliba Susan A. , Hart Joseph M.
Published: May 2015

Context

Individuals with a history of anterior cruciate ligament reconstruction (ACLR) are at greater risk of reinjury and developing early-onset osteoarthritis due to persistent abnormal joint loading. Real-time clinical assessment tools may help identify patients experiencing abnormal movement patterns after ACLR.

Objective

To compare performance on the Landing Error Scoring System (LESS) between participants with ACLR and uninjured control participants and to determine the relationship between LESS score and knee-extension strength in these participants.

Design

Controlled laboratory study.

Setting

Research laboratory.

Patients or Other Participants

Forty-six recreationally active participants, consisting of 22 with ACLR (12 men, 10 women; age = 22.5 ± 5.0 years, height = 172.8 ± 7.2 cm, mass = 74.2 ± 15.6 kg, body mass index = 24.6 ± 4.0) and 24 healthy control participants (12 men, 12 women; age = 21.7 ± 3.6 years, height = 168.0 ± 8.8 cm, mass = 69.2 ± 13.6 kg, body mass index = 24.3 ± 3.2) were enrolled.

Main Outcome Measure(s)

Bilateral normalized knee-extension maximal voluntary isometric contraction (MVIC) torque (Nm/kg) and LESS scores were measured during a single testing session. We compared LESS scores between groups using a Mann-Whitney U test and the relationships between LESS scores and normalized knee-extension MVIC torque using Spearman ρ bivariate correlations.

Results

The ACLR participants had a greater number of LESS errors (6.0 ± 3.6) than healthy control participants (2.8 ± 2.2; t44 = −3.73, P = .002). In ACLR participants, lower normalized knee-extension MVIC torque in the injured limb (ρ = −0.455, P = .03) was associated with a greater number of landing errors.

Conclusions

Participants with ACLR displayed more errors while landing. The occurrence of landing errors was negatively correlated with knee-extension strength, suggesting that weaker participants had more landing errors. Persistent quadriceps weakness commonly associated with ACLR may be related to a reduced quality of lower extremity movement during dynamic tasks.
Memory and historical Jesus studies: Formgeschichte  in a new dress?
Authors: Van Eck Ernest
Published: May 2015

In the quest for the historical Jesus, memory studies are seen as an important breakthrough in the study of the historical Jesus and the way forward in establishing the historicity of the Gospel traditions. This article evaluates the claim made by memory studies by evaluating memory studies’ critique on the methodology of the criteria approach. In this evaluation attention is given to the methodological points of departure of memory studies, including an assessment of the few examples memory studies thus far have produced in their investigation of the historicity of the Gospels and the historical Jesus. The conclusion reached is that memory studies are guilty of what they accuse the criteria approach, and thus far have not yet offered a viable methodological alternative to the current criteria approach used in historical Jesus research.
Metastatic Bone Pain Palliation using 177 Lu-Ethylenediaminetetramethylene Phosphonic Acid
Authors: Alavi Mehrosadat , Omidvari Shapour , Mehdizadeh Alireza , Jalilian Amir , Bahrami-Samani Ali
Published: May 2015

177 Lu-ethylenediaminetetramethylene phosphonic acid (EDTMP) is presently suggested as an excellent bone seeking radionuclide for developing metastatic bone pain (MBP) palliation agent owing to its suitable nuclear decay characteristics. To find the exact dosage and its efficiency, this clinical study was performed on the human being, using 177 Lu-EDTMP for MBP palliation. 177 Lu-EDTMP was prepared by Iran, atomic energy organization. Thirty consecutive patients with determined tumors, incontrollable MBP, and positive bone scan at 4 weeks before the beginning of the study participated in this study in the nuclear medicine ward. 177 Lu-EDTMP in the form of sterile slow IV injection was administered with a dose of 29.6 MBq/kg. Short form of brief pain inventory questionnaire was used to evaluate the efficiency of the intervention. Questionnaires were filled out by an expert nuclear physician every 2 weeks while the cell blood count was also checked every 2 weeks up to 12 weeks for evaluation of bone marrow suppression and hematological toxicity. Furthermore, whole body scan was done at days 1, 3, and 7. Twenty-five patients showed a significant pain relief since 2 weeks after the injection, and continued until the end of the follow up period (12 weeks). There were no significant early complications such as bone marrow suppression, hematological toxicity, and no systemic adverse effects. No complication was observed in renal function. Twenty one patients showed flare phenomenon that was started after the 12.2 ± 1.78 h lasting for 38.4 ± 23.08. Sixteen patients (53%) were completely treated; nine patients (30%) showed a partial response, and five patients (17%) had no response to treatment. Total response to treatment was achieved in 25 patients (83%). At the end of the evaluation, no bone marrow suppression or hematologic toxicity was observed. 177 Lu-EDTMP has shown suitable physical and biological properties with good results in long term bone pain relief for patients with bone metastasis.
A Comprehensive Profile of ChIP-Seq-Based Olig2 Target Genes in Motor Neuron Progenitor Cells Suggests the Possible Involvement of Olig2 in the Pathogenesis of Amyotrophic Lateral Sclerosis
Authors: Satoh Jun-Ichi , Asahina Naohiro , Kitano Shouta , Kino Yoshihiro
Published: May 2015

Background

Amyotrophic lateral sclerosis (ALS) is an intractable neurodegenerative disease that primarily affects motor neurons in the cerebral cortex and the spinal cord. Recent evidence indicates that dysfunction of oligodendrocytes is implicated in the pathogenesis of ALS. The basic helix–loop–helix (bHLH) transcription factor Olig2 plays a pivotal role in the development of both motor neurons and oligodendrocytes in the progenitor of motor neuron (pMN) domain of the spinal cord, supporting evidence for the shared motor neuron/oligodendrocyte lineage. However, a comprehensive profile of Olig2 target genes in pMNs and oligodendrocyte progenitor cells (OPCs) with relevance to the pathogenesis of ALS remains to be characterized.

Methods

By analyzing the ChIP-Seq datasets numbered SRP007566 and SRP015333 with the Strand NGS program, we identified genome-wide Olig2 target genes in pMNs and OPCs, followed by molecular network analysis using three distinct bioinformatics tools.

Results

We identified 5966 Olig2 target genes in pMNs, including Nkx2.2, Pax6, Irx3, Ngn2, Zep2 (Cip1), Trp3, Mnx1 (Hb9), and Cdkn1a, and 1553 genes in OPCs. The genes closely related to the keyword “alternative splicing” were enriched in the set of 740 targets overlapping between pMNs and OPCs. Furthermore, approximately one-third of downregulated genes in purified motor neurons of presymptomatic mutant SOD1 transgenic mice and in lumbar spinal cord tissues of ALS patients corresponded to Olig2 target genes in pMNs. Molecular networks of Olig2 target genes indicate that Olig2 regulates a wide range of genes essential for diverse neuronal and glial functions.

Conclusions

These observations lead to a hypothesis that aberrant regulation of Olig2 function, by affecting biology of both motor neurons and oligodendrocytes, might be involved in the pathogenesis of ALS.
Ninjas, princesas y robots gigantes: género, formato y contenido en el manganime
Authors: Torrents Alba G.
Published: May 2015

Este artículo se sirve de las nociones veronianas de género-L y género-P para intentar aportar un poco de luz a la problemática de la clasificación de géneros en el manga y el anime. Para ello, se adopta
estratégicamente la distinción entre género-L y género-P, aplicándola al manga y al anime, para mostrar a continuación que la aplicación de dichas categorías veronianas a este campo de producción cultural japonés es mucho más problemática de lo que puede parecer en un principio.
Freud and Nietzsche
Authors: Assoun Paul-Laurent
Published: May 2015

Many of the leading Freudian analysts, including in the early days, Jung, Adler, Reich and Rank, attempted to link the writings of Nietzsche with the clinical work of Freud. But what was Nietzsche to Freud – an intuitive anticipation, a precursor, a rival psychologists? Assoun moves beyond the seduction of these attractive analogies to a deeper analysis of the relation between these two figures. He reconstructs Freud’s encounter with Nietzsche, his personal interpretations and the contribution of Nietzsche’s champions. He also examines the thematic similarities that appear on th surface to reveal close affinities between the theorists. His argument is that these “analogies” are really the symptom of an open, ongoing dialogue between Freud and Nietzsche (and Marx) which remains vital to critical theory today.
Time of day and season affect the level of noise made by pigs kept on slatted floors
Authors: Sistkova M. , Dolan A. , Broucek J. , Bartos P.
Published: May 2015

Abstract. The aim of this study was to prove the hypothesis that the noise emissions from pig housing varies according to the time of day and the season. The measurements were performed in a building for 1150 fattening pigs with a slatted floor during summer and winter. The pigs (average weight 95 kg) were kept in pens under a batch management system. Nine places were the focus of sound intensity measurements (one inside the stable in section 7; eight places outside the building). The measurements were performed during three sets of 5 consecutive days in summer and three sets in winter. On each day the data were obtained during three 30 min periods (before feeding, during feeding and after feeding). The measurement was made inside and outside the building at the same time. The level of noise depends very significantly upon the period of measurement (before feeding, during feeding, after feeding). The following values were recorded inside (place 1): 65.5 ± 1.6 dB before feeding, 72.0 ± 1.4 dB during feeding and 63.4 ± 0.7 dB after feeding (P < 0.001). The effect of seasonal noise levels can be seen only in outside measurements (P < 0.05; P < 0.01). The comparison of measurement place 1 (inside, pen with pigs) with the other places outdoors showed significant differences in both observed factors (P < 0.001). We can conclude that the noise in the pig housing depends significantly on the time of day. The season influences the noise outside the building, in particular.
Intercomparison of two Comparative Reactivity Method instruments in the Mediterranean basin during summer 2013
Authors: Zannoni N. , Dusanter S. , Gros V. , Sarda Esteve R. , Michoud V. , Sinha V. , Locoge N. , Bonsang B.
Published: May 2015

Abstract. The hydroxyl radical (OH) plays a key role in the atmosphere, as it initiates most of the oxidation processes of Volatile Organic Compounds (VOCs), and can ultimately lead to the formation of ozone and Secondary Organic Aerosols (SOA). There are still uncertainties associated with the OH budget assessed using current models of atmospheric chemistry and direct measurements of OH sources and sinks have proved to be valuable tools to improve our understanding of the OH chemistry. The total first order loss rate of OH, or total OH reactivity, can be directly measured using three different methods, such as: total OH Loss rate Measurement, Laser Induced Pump and Probe Technique and Comparative Reactivity Method. Observations of total OH reactivity are usually coupled to individual measurements of reactive compounds in the gas phase, which are used to calculate the OH reactivity. Studies using the three methods have highlighted that a significant fraction of OH reactivity is often not explained by individually measured reactive compounds and could be associated to unmeasured or unknown chemical species. Therefore accurate and reproducible measurements of OH reactivity are required. The Comparative Reactivity Method (CRM) has demonstrated to be an advantageous technique with an extensive range of applications, and for this reason it has been adopted by several research groups since its development. However, this method also requires careful corrections to derive ambient OH reactivity. Herein we present an intercomparison exercise of two CRM instruments (CRM-LSCE and CRM-MD), conducted during July 2013 at the Mediterranean site of Ersa, Cape Corsica, France. We discuss in detail the experimental approach adopted and how the data sets were processed for both instruments. Corrections required for the two instruments lead to higher values of reactivity in ambient air; overall 20% increase for CRM-MD and 49% for CRM-LSCE compared to the raw data. We show that ambient OH reactivity measured by the two instruments agrees very well (correlation described by a linear least squares fit with a slope of 1 and R2 of 0.75). This study highlights that ambient measurements of OH reactivity with differently configured CRM instruments yield consistent results in a low NOx, terpene rich environment, despite differential corrections relevant to each instrument. Conducting more intercomparison exercises, involving more CRM instruments operated under different ambient and instrumental settings will help in assessing the variability induced due to instrument specific corrections further.
Drought-influenced mortality of tree species with different predawn leaf water dynamics in a decade-long study of a central US forest
Authors: Gu L. , Pallardy S. G. , Hosman K. P. , Sun Y.
Published: May 2015

Abstract. Using decade-long continuous observations of tree mortality and predawn leaf water potential (ψpd) at the Missouri Ozark AmeriFlux (MOFLUX) site, we studied how the mortality of important tree species varied and how such variations may be predicted. Water stress determined inter-annual variations in tree mortality with a time delay of 1 year or more, which was correlated fairly tightly with a number of quantitative predictors formulated based on ψpd and precipitation regimes. Predictors based on temperature and vapor pressure deficit anomalies worked reasonably well, particularly for moderate droughts. The exceptional drought of the year 2012 drastically increased the mortality of all species, including drought-tolerant oaks, in the subsequent year. The drought-influenced tree mortality was related to the species position along the spectrum of ψpd regulation capacity with those in either ends of the spectrum being associated with elevated risk of death. Regardless of species and drought intensity, the ψpd of all species recovered rapidly after sufficiently intense rain events in all droughts. This result, together with a lack of immediate leaf and branch desiccation, suggests an absence of catastrophic hydraulic disconnection in the xylem and that tree death was caused by significant but indirect effects. Species differences in the capacity of regulating ψpd and its temporal integral were magnified under moderate drought intensities but diminished towards wet and dry extremes. Severe droughts may overwhelm the capacity of even drought-tolerant species to maintain differential levels of water potential as the soil becomes exhausted of available water in the rooting zone, thus rendering them more susceptible to death if predisposed by other factors such as age.
Multi-century lake area changes in the Andean high-elevation ecosystems of the Southern Altiplano
Authors: Morales M. S. , Carilla J. , Grau H. R. , Villalba R.
Published: May 2015

Abstract. High-elevation endorreic lakes in the Southern Altiplano of South America represent a major source of local biodiversity. Size and depth of wetlands in Northwest Argentine (NWA) and Southwest Bolivia (SWB) have shown to be very sensitive to basin hidrological balances, and consequently, very vulnerable to deleterious effects from climate changes. The management of these water resources requires a comprehensive knowledge of their natural variability over multiple time scales. In this study we present a multi-century reconstruction of past lake-area fluctuations in the NWA and SWB, inferred from Polylepis tarapacana tree-ring records. Between 1975 and 2009 interannual lake area fluctuations from nine lakes were quantified based on Landsat satellite images. A composite P. tarapacana tree-ring chronology was developed. Correlations analyses were performed to screen potential predictor tree-ring chronologies for reconstruction models. Inter-annual lake area fluctuations were positively correlated with inter-annual variations of the radial growth of P. tarapacana. A tree-ring chronology (601 years long) was use as predictor, in a regression model, to reconstruct the annual (January–December) mean lake area from nine endorreic lakes. The chronology captures 60% of the total variance in lake-area fluctuations and shows adequate levels of cross-validation. The twentieth century was unusual in the long-term context provided by the reconstruction; a persistent negative trend in lake area is clear in the reconstruction during the past century and is consistent with glacier retreat and other climate proxies from the Altiplano and tropical Andes. These results provide a baseline for the historical range of variability in lake fluctuations, and thus should be considered for the management of biodiversity and water resources in the region, particularly in relation to future XXI century climate scenarios.