bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of SiC Particles on Microstructure and Wear Behavior of AA6061-T6 Aluminum Alloy Surface Composite Fabricated by Friction Stir Processing
Authors: Abbass Muna Khethier , Baheer Noor Alhuda
Published: January 2020

This research studies the effect of SiC particles on the microstructure and wear behavior of AA6061-T6 aluminum alloy surface composite. Friction stir processing (FSP) was used to incorporate micro-sized SiC particles into AA6061-T6 aluminum alloy to form a particulate composite surface layer. Samples were subjected to two passes of FSP with and without SiC powder at the best rotational speed of 1250 rpm, travel speed of 32 mm/min and two passes in the same direction. Microstructural observations were conducted via optical and scanning electron microscopy (SEM) of samples subject to FSP. Mechanical properties, including microhardness and wear resistance, were evaluated. The results manifested that at two passes, the FSP caused a more uniformity in the distribution of SiC particles. The addition of SiC particles to AA6061-T6 improved the hardness (improvement 62.6%) and wear resistance as compared to FSPed sample without SiC particles. The wear behavior was of a mild type or an oxidative type at low loads (5 N), which became severe or metallic wear at higher loads (20 N) for sliding time 20 min.
Improvement of Mechanical Properties of Magnesium (Mg) Matrix Composites Reinforced with Nano Alumina (Al2O3) Particles
Authors: Abed Zaid Hayder Muneam , Abed Abdul Rahman N. , Hasan Hala Salman
Published: January 2020

Nano alumina particle-reinforced magnesium was fabricated by powder metallurgy technique. Powders were mixed by ball milling (without balls) for 6 hours at rotation speed 60 rpm. Then, the powder was compacted at 550 MPa and sintered at 530°C for 2 hours. The magnesium contained 0.25, 0.5, 1, 1.5, 3, and 5 vol. % nano alumina Al2O3. The physical, mechanical properties and microstructures, such as density, porosity, compressive strength, hardness, wear rate, SEM and EDX, were measured and compared with the values of unmodified pure magnesium samples. The results revealed an improvement with Al2O3 in Mg matrix composites. The greatest improvement in UCS and Hv values were about 197 MPa and 70 Hv at the volume fraction of 3 vol.% Al2O3 respectively. The wear tests showed that wear resistance was increased with the increasing of the reinforcement volume fraction of Al2O3.
Study of bending resistance of sandwich structures
Authors: Šuba O , Kubišová M , Šuba O , Měřínská D , Pitnerová L
Published: January 2020

Article deals with the study of the flexural limit state of sandwich structures based on fiberglass and polymeric foams. Whether geometrical and material parameters influence the resulting load-bearing capacity of these structures are studied experimentally using FEM models. This study shows it is necessary to particular emphasis attention to the issue of flexural strength, the load capacity when of the walls designing sandwich shell products to avoid possible failures in the practical use of these types of structures. Subsequently, Horn’s evaluation method is used to compare the experimental testing and the FEM model.
The Influence of the Three-Layer Mouthguard on the Stress-Strain State of a Pair of Opposing Teeth
Authors: Avdeeva E S , Kamenskikh A A
Published: January 2020

The aim of the study was to consider the contact interaction of a pair of opposing teeth with and without taking into account the three-layer mouthguard. The strain-stress analysis of the biomechanical model was undertaken within the framework of the elastoplastic stress-strain theory. 7 geometric configurations of the mouthguard were considered within a wide range of functional loads which were varied from 50 to 500 N. We obtained the distribution of the stress and strain intensities in a pair of opposing teeth during contact interaction at a different level of physiological load. The dependences of the maximum level of stress intensity and the intensity of plastic deformations in the biomechanical model were established. Contact parameters were considered near the zone of dental occlusion.
Influence of a Delamination Defect Location on the Operating Life of a Multi-Layered Composite Sample
Authors: Anoshkin A N , Pisarev P V , Ermakov D A
Published: January 2020

In the framework of this research, the authors proposed an algorithm for predicting the residual life of structures made of polymer composite materials (PCM) using the structural-phenomenological model. To assess the residual life of PCM structures under cyclic loading, it was proposed to use the approach of explicit description of the adhesive layers destruction process. In accordance with the developed algorithm, in the process of cyclic loading in the adhesive layers, the level of damage was recorded; upon reaching a critical damage level, the adhesive layers destruction was simulated. The algorithm was tested on sample structures with a defect in the form of delamination and without defects. A numerical study of the delamination defect location influence at the onset of fatigue failure of model structures was carried out.
Nanostructuring of a Surface Layer as a Way to Improve the Mechanical Properties of Hypoeutectic Silumin
Authors: Kondratyuk A A , Ivanov Yu F , Klopotov A A , Ustinov A M , Abzaev Yu A , Petrikova E A , Teresov A D , Tolkachev A S
Published: January 2020

The irradiation of hypoeutectic silumin 383.1 with an intense pulsed electron beam in the melting mode and rapid crystallization of the surface layer has been performed. A multiphase submicron nanostructured surface layer with a thickness of up to 70 nm has been formed. Mechanical tests of the irradiated silumin samples in tensile experiments have been carried out. A significant increase in strength and plastic properties of silumin irradiated with an electron beam has been established. Features and patterns in the distribution of displacement fields in the deformation process in surface layers of the samples in realtime have been identified by digital image correlation method using the optical measuring system VIC-3D.
Increasing Fatigue LIfe of 09Mn2Si Steel by means of High-Temperature Multistep Helical Rolling
Authors: Vlasov I V , Surikova N S , Panin S V , Yakovlev A V , Gomorova J F
Published: January 2020

The effect of high temperature helical rolling (HR) on structure and fatigue life of 09Mn2Si pipe steel has been studied. With the use of transmission electron microscopy there was revealed that rolling gives rise to refinement of ferrite grains and cracking (fracturing) of cementite plates within the pearlite phase. The effect manifests itself to the greatest extent in the surface layer where due to the rolling the level of plastic deformation was the highest. Data of microhardness measurements confirms the gradient pattern of strain hardening over the cross section during the HR occurs while the most intensive microhardness increasing take place at the depth of up to 3 mm. According to the mechanical testing results the helical rolling of 09Mn2Si steel gives rise to increasing the level of deforming stress at the yield plateau as well as the proportionality limit with a general decrease in the relative elongation. At the same time, despite the strain hardening resulting from the helical rolling the mechanisms of plastic deformation which manifest themselves in the form of parabolic hardening with a smooth decrease in the flow stress level after neck formation are preserved in the steel. During the cyclic tension the number of cycles prior to failure increases from 2.5 to 3.8 times that depends on the location of specimens’ cutting from the rolled rod. The highest improvement in fatigue fracture resistance is registered for specimens cut out from the core of the rolled rods.
Nonwoven PTFE Membranes Fabricated by Electrospinning Method: Preparation and Characterization
Authors: Kolesnik I M , Bolbasov E N , Buznik V M , Tverdokhlebov S I
Published: January 2020

Polytetrafluoroethylene (PTFE) is one of the promising materials for the purposes of tissue engineering and chemical technology because of its excellent physico-chemical properties and mechanical characteristics. However, conventional methods of PTFE porous membranes production have several disadvantages which limit the number of potential application areas by reason of a insufficient surface-to-volume ratio and poor porosity at small thickness. In the paper the results of using PTFE water suspension with a solution of water-soluble polymer for preparation of porous membranes by electrospinning are reported. The physico-chemical characteristics of membranes were investigated depending on the content of PTFE dispersion in spinning solution. There were found high hydrophobicity and lyophilicity of PTFE electrospun membranes. Main reasons of poor mechanical properties of porous membranes at high content of PTFE suspension in spinning solution are discovered. The ways of mechanical properties improvement and areas of possible applications are proposed.
Composition Polymeric Membranes Based on the VDF-TeFE Copolymer Formed by Electrospinning
Authors: Tverdokhlebova T S , Bolbasov E N , Bouznik V M
Published: January 2020

The paper presents the results of pilot studies on the formation of non-woven hydrophilic piezoelectric composite polymer membranes based on a copolymer of vinylidene fluoride and tetrafluoroethylene (VDF-TeFE) and polyethenylpyrrolidine (PEP) by electrospinning. Using optical goniometry, the effect of the PEP content on the wetting of the membrane surface with water was established. Using scanning electron microscopy, the influence of the content PEP on the structure of the formed membranes was studied. The effect of an isotonic NaCl solution on the structure of the formed membranes upon their dissolution within 7 days was studied. Based on studies of the chemical composition of the membranes before and after their dissolution, an assumption was made about the possibility of using the developed membranes for targeted delivery of pharmacological preparations for wound healing.
The Hydrothermal Synthesis Duration Influence on Calcium Phosphate and Hydroxyapatite Phase Composition
Authors: Chuprunov K , Yudin A , Leybo D , Lysov D , Kolesnikov E , Kuznetsov D , Godymchuk A , Mandal A R
Published: January 2020

This paper reports the hydrothermal synthesis process duration influence on phase composition, crystallinity degree, morphology and dispersity of the hydroxyapatite powder. The calcium phosphate and hydroxyapatite were synthesized in precursor system Ca(NO3)2-(NH4)2HPO4-NH4OH. The obtained powders were characterized with X – Ray diffraction, Fourier Transform spectroscopy (FTIR) and Raman spectroscopy. The results demonstrate: the increasing of the synthesis time duration has no influence on the phase composition. However, the synthesis duration time growth from 12 to 48 hours make possible increase the crystallinity degree from 0.68 to 0.98.
Effect of Surface Burnishing Treatment on Microstructure and Wear Performance of ZK60 Magnesium Alloy
Authors: Zhang Haiquan , Liu Yichen , Guo Peiquan
Published: January 2020

In order to improve the surface properties of high strength magnesium alloy ZK60, the surface burnishing treatment was carried out. The effects of burnishing process parameters on surface roughness, microhardness and microstructure of ZK60 magnesium alloy were studied. And the wear performance of the untreated and the surface burnishing treated samples was compared and analyzed. A gradient microstructure layer of nanocrystalline, ultrafine, deformed and original coarse grains from the treated surface to the matrix was formed on ZK60 alloy by surface burnishing treatment. In comparison with the untreated sample, the surface roughness of the burnishing treated sample was significantly reduced and the surface microhardness was evidently improved. After surface burnishing treatment, the wear of ZK60 sample decreased by 44.58%, and the friction coefficient decreased from 0.328 to 0.293, significantly improving the wear performance.
Preparation and Characterization of Submicron TiO2 Microspheres via Urea-formaldehyde Template
Authors: Lin Shaosen , Du Shiguo , Lu Yanling
Published: January 2020

In order to obtain sub-micron TiO2 microspheres with good dispersibility and easy collection, urea-formaldehyde(UF)-TiO2 hybrid microspheres were synthesized by polymerization-induced precipitation in acidic TiO2 sol through the reaction of urea and formaldehyde. The hybrid microspheres and their calcined products were analyzed by scanning electron microscopy, laser particle size analyzer, thermogravimetric analyzer and X-ray Powder diffractometer. The results of morphological characterization showed that the UF-TiO2 hybrid microspheres were spherical and well dispersed, and their particle size ranged from 0.8∼5μm The sub-micron TiO2 microspheres with large pore volume and good dispersion were obtained by calcining and removing the organic components in the hybrid microspheres. Thermogravimetric analysis showed that the proportion of inorganic components in hybrid microspheres was about 20%. XRD analysis showed that the product of calcined hybrid microspheres was single anatase-type titanium dioxide.
Analytic Solutions of Two-photon Rabi Model Based on Bargmann Space
Authors: Yan Zhanyuan , Yao Xuemin
Published: January 2020

The quantum Rabi model (QRM) is identified as the simplest model to study the interaction between light and matter. In recent years, Braak proposed an alternative more efficient method to obtain the exact solvability and spectrum of the QRM in the Bargmann space, which is appropriate frame for extended squeezed coherent states. Based on this feasible method, some study for the two-photon QRM is concentrated. In this paper we diagonalized the Hamiltonian and obtain the Spectrum of the system of two-photon QRM in the special case that the level splitting of the atom was equal to 0, and compared with Travĕnec’s results without diagonalizing the Hamiltonian. Finally, we confirm the validity of diagonalization for the Hamiltonian in the two-photon QRM.
Preparation and Electrochemical Performance of Porous Si/SiOx/G Composite Anode for Lithium Ion Batteries
Authors: Wang Jing , Zhang Xiaoyan , Wang Ran , Tan Guoqiang , Su Yuefeng , Wu Feng
Published: January 2020

Silicon/silicon oxides/graphite (Si/SiOx/G) composite with high capacity and excellent cycling performance has been synthesized via high temperature treatment, HF etching and high-energy ball milling for mixture of silicon oxide and graphite. The chemical composition and morphology of the sample was characterized by XRD, SEM and TEM. Large numbers of nanopores were formed in the as-prepared composite, providing three-dimensional transmission pathways for lithium ions and electrons. After 100 cycles, the electrode kept an excellent reversible capacity of 804.2mAh·g-1. The excellent electrochemical properties are mainly attributed to the uniform distribution of silicon particles in amorphous silicon oxide, the buffering effect of porous structure and the improvement of conductivity of the composite by graphite.
Development Trend of Low Thermal Conductivity Ceramic Materials
Authors: Luo Xiqian , Guo Bohan , Wang Xiaoqiang , Zhang Zeyu
Published: January 2020

In recent years, high entropy ceramics have become one of the research hot spots in the ceramic field due to its superior high entropy characteristics, and the use of blast furnace slag as high entropy material is also in line with the general trend of energy conservation and emission reduction in today’s society. This paper will briefly introduce the preparation and properties of several common porous ceramics by studying the low thermal conductivity mechanism of traditional ceramic materials. The high entropy ceramic materials are further introduced. By introducing its low thermal conductivity principle, preparation process and its low thermal conductivity related experiments, the superior performance of low thermal conductivity high entropy ceramic materials compared with traditional porous materials is demonstrated, the development trend of low thermal conductivity ceramic materials is analyzed, and finally the application prospect of blast furnace slag in high entropy materials is prospected.
Volumetric Displacement in Large Deflection of Symmetrically Layered Piezoelectric Plate under Pretension
Authors: Chen Chunfu , Yu Hsiangjuei
Published: January 2020

The volumetric displacement of a simply supported and symmetrically layered piezoelectric circular plate under lateral load and pretension in large deflection is studied. The approach extends von Karman’s large deflection theory to a layered case and accounts for the associated piezoelectric force terms. The nonlinear governing equations based on the equilibrium were derived, but the arising nonlinear terms in governing equations were dropped, to have an analytical investigation. The solutions were found to be expressible with modified Bessel or standard Bessel functions, depending on whether it is a mechanical-load dominating or piezoelectric-load dominating condition. The previously derived expressions for lateral slopes and deflections are further manipulated to derive the analytical expressions for the volumetric displacements, following strictly the related recurrence relations. The presented approaches are implemented with typical silicon-based layer materials used in a sensing or actuating device. Various dimensions, especially the relative thickness of the piezoelectric layer, as well as different applied voltages and pretensions are considered to have an extensive parametric study. The results indicate that, piezoelectric effect is only apparent in a low pretension condition. Upon reaching a moderate pretension, the pretension effect may always be dominant over the effects of varying the applied voltage and relative thickness.
Study on the Corrosion Inhibition of Benzotriazole in the Blast Furnace Gas Condensate Water
Authors: Gao Yuhua , Li Haihua , Zhang Lihui , Liu Zhenfa
Published: January 2020

Preparation of the corrosion inhibitor was carried out by adding the benzotriazole in sodium hydroxide solution in view of the corrosion problem of blast furnace gas condensate in iron and steel enterprises. Real-time corrosion rate of blast furnace gas condensate water with and without the corrosion inhibitor was monitored throug corrosion rate tester. The average real time corrosion rates of the blast furnace gas condensed water contacting the various dosage of the corrosion inhibitor were lower than the average real time corrosion rates without adding the corrosion inhibitor. Corrosion inhibition behavior of the corrosion inhibitor on carbon steel in the blast furnace gas condensed water using weight loss measurement method.
Research on the Losing Process of the Traditional Gray Bricks and Tiles
Authors: Zhao Peng , Qin Lei , Zhang Xiuzhi , Zhang Yunsheng , Ren Hongwei , Lv Yinghui , Liu Gengle
Published: January 2020

Gray bricks and tiles are important materials of traditional buildings in China. However, the production process of bricks and tiles uses a large amount of clay resources from cultivated land, consumes a large amount of energy such as coal, and at the same time causes a great load to the environment. Therefore, the production process of traditional gray bricks and tiles is facing the risk of loss. This study investigates the traditional brick and tile manufacturers in Jiangsu and Zhejiang provinces and records the manufacturing techniques of traditional brick and tile blanks in detail, providing detailed records for the protection and repair of the architectural heritage.
Damage Process of High-piled Wharf Subjected to Underwater Explosion
Authors: Liu Jinghan , Tang Ting , Wei Zhuobin , Li Lingfeng
Published: January 2020

In order to study the damage process of high-piled wharf subjected to underwater explosion, analysis model of high-piled wharf was established. The load characteristics of piles and panel of high-piled wharf were analysed during shock wave propagation and bubble pulse. The failure mode of wharf is basically completed in the first bubble pulse. The damage effect at the top of the pile is the most serious, the damage at the middle is slight, and the damage at the bottom is the weakest. Concrete damage occurs at the connection between pile and beam, beam and longitudinal beam. As the depth of explosive decreases, the damage effect of piles decreases and the damage effect of wharf superstructure increases. When the explosive explodes near the water surface, the wharf panel is damaged seriously and ultimately unusable.
Design of Ionic Fog Filter for AC-1 Machining Center
Authors: Zhou Quan , Xie Yonghui , Chen Juan
Published: January 2020

In the process of modern NC machine tool processing, a large number of oil fog, smoke, containing polychlorinated biphenyls (PCBs) are produced, which is easy to cause toxic fog and seriously harm the health of staff. This paper introduces the design of an oil mist suction device to avoid the diffusion of toxic fog for a long time, to create a comfortable working environment, to prolong the life of machine tool equipment and to improve the production efficiency. It has been proved by application that it meets the performance requirements of modern NC machining center and obtains good social and economic benefits.
The Effect of Aluminum Ions on the Acidification and Aging of Paper
Authors: Zhang Hongwei , Zhai Pengchen , Wang Qinwen , Li Yanqin , Tang Aimin
Published: January 2020

Paper documents provide important records of human civilization and so understanding the causes of paper document aging is very important to delay the process and prolong the lifespan of paper. This study used an anionic rosin as a sizing agent and aluminum sulphate as a fixing agent, to produce paper with different amounts of aluminum sulphate. The effect of different contents of aluminum ions on the acidification and aging of the paper was studied by accelerated aging experiments. The results showed that the presence of aluminum ions in paper could accelerate the acidification and aging process, and the higher the content of aluminum ions, the worse the durability of paper. In the process of accelerated aging, with increasing aluminum ion content, the rate of decline in the strength and whiteness of paper increased whilst the pH value decreased. Accelerated aging under the same conditions for 15 days caused the pH value, whiteness, tensile index and tear index of paper without aluminum ions to decrease by 14.77%, 3.15%, 7.99% and 11.70% respectively. In comparison, paper which had aluminum sulphate added to 30 kg per ton of paper, showed the decreases of pH, whiteness, tensile index and tear index by 22.62%, 4.35%, 24.66% and 31.07% respectively.
Assembling Construction Technology of Prefabricated Box Culvert Components
Authors: Kang Yumei , Zhang Naiyuan , Wang Tao , Song Yuhang
Published: January 2020

Box culverts are common small structures in highway engineering. According to domestic and foreign practical experience in recent years, component factory prefabrication combined with on-site assembly can effectively improve production efficiency and construction quality. It will become the main trend in the box culvert structure and gradually replace the traditional cast-in-place process. Based on the project of 03A design section of Daqing to Guangzhou Expressway, this paper expounds in detail the assembly process and key operation points of prefabricated components. It also compared with the traditional culvert construction technique, which demonstrates the superiority of prefabricated box culvert assembly technology.
Review of GIS Technology and Its Applications in Different Areas
Authors: Liu Ziye , Cheng Liusan
Published: January 2020

The 21st century, with the rapid development of information technology (IT), digital life gradually penetrated into every aspect of production and life. To investigate the use of digital life, each country throughout the world, including of China, started planning for digital nation and digital city project. Effective information tools, such as geographic information system (GIS), help to deal with spatial data and complex interactions in city and nation construction. In order to systematically realize the goal of urban planning and constantly promote the level of urbanization, this literature is reviewed for the applications of GIS in the past, of land management, urban and rural planning, traffic management and environmental management. Besides, it puts forward the digital nation expect of GIS applications in the future.
Effect of Peg on Polysulfone Support and Reverse Osmosis Membrane Property
Authors: Wang Jin , Zhang Zhijie , Li Jiarui , Zhu Jiani , Meng Xiaorong , Li Xiaojun , Wang Xudong
Published: January 2020

A study on the thin film composite on polysulfone support membranes prepared by different casting solution was conducted. The following conclusions can be drawn from this work, the membrane flux increased with increasing PEG concentration and the pore size and the porosity on the membrane surface became bigger by the increase PEG concentration; the permeability of thin film composite membrane was effected by the membrane continuity and the amount of polyamide formed within PSf membrane pores.
Reform of University Physics Experiment Course under the Combination of Big Data and Industrial Internet
Authors: Han Chunjuan
Published: January 2020

This paper puts forward the combination of big data and university physics experiment teaching based on the combination of big data and industrial internet, and tries to get rid of the traditional teaching mode of university physics experiment and develop innovative experiment teaching, focusing on the application of computer data acquisition and data analysis in the process of university physics experiment teaching. Let our students, like scientists and engineers, open up the relevant concepts in reality in their study, reduce the chance of gross errors in the experiment process, use cloud computing to achieve real-time data feedback, improve the understanding of concepts, increase students’interaction, and promote students’ thinking, thus becoming active participants, allowing students to spend more time in analysis and development. High-level thinking skills.
Microstructure and hot corrosion behavior of hot dip siliconized coating on Ni-base superalloy IN738LC
Authors: Targhi Vahid Tavakoli , Omidvar Hamid , Hadavi Seyed Mohammad Mehdi , Sharifianjazi Fariborz
Published: January 2020

Nickel-based superalloys are widely used at elevated temperature applications because of their high corrosion and oxidation resistance characteristics as well as high stability. To improve the hot corrosion resistance of Nickel-based superalloys, different coatings are applied. In this study, nickel-base superalloy Inconel 738LC was coated via a novel hot-dip diffusion siliconizing process and the corrosion behavior was investigated by XRD, SEM and EDS analyses. A sever degradation and poor hot corrosion resistance was detected by the uncoated sample, while the siliconized coated sample possessed high corrosion resistance. It was figured out that the high hot corrosion resistance of the coated sample was due to the formation of SiO2 protective scale in the surface layer which protects the substrate elements in the hot corrosion environment.
Structure and electrical conductivity properties of K doped Sr1−xKx(Sr0.50Nb0.50)O2.75−δ complex perovskites
Authors: Karuppiah Kavitha , Raja Althaf , Ojha Prasanta Kumar , Deepika C Lakshmi , Ashok Anuradha M
Published: January 2020

In the present study structural and electrical conductivity properties of complex perovskites with general formula Sr1−x
K
x
(Sr0.50Nb0.50)O2.75−δ
have been studied. Potassium is doped in the cuboctahedral Sr site Sr1−x
K
x
(Sr0.50Nb0.50)O2.75−δ
with different dopant concentrations such as x = 0, 0.25, 0.50, 0.75 and 1. The structural and morphological properties of Sr1−x
K
x
(Sr0.50Nb0.50)O2.75−δ
were studied using Thermogravimetry (TG) analysis, x-ray diffraction (XRD) and Scanning electron microscopy (SEM). Electrochemical impedance spectroscopy (EIS) was performed to investigate the electrical properties. The effect of structural and morphological variations associated with the dopant concentration affecting the electrical conductivity behaviour of Sr1−x
K
x
(Sr0.50Nb0.50)O2.75−δ
complex perovskite oxides were studied in detail. The higher total conductivity was observed for 100% K doped (x = 1, 3.10 × 10−5 S cm−1at 800 °C) and 25% K doped (x = 0.25, 2.02 × 10−5 S cm−1at 800 °C) composition.
Inhibiting degradation of LiCoO2 cathode material by anisotropic strain during delithiation
Authors: Xiang Qianxin , Li Lu , Wang Lijuan , Zhou Chaoyi , Zhang Dongyan , Li Zhimin
Published: January 2020

Lithium cobalt oxides (LiCoO2) possess a high theoretical specific capacity of 274 mAhg−1. However, when LiCoO2 is charged at the voltage higher than 4.2 V, there exist significant structure transition and capacity fade. In this study, we used HRTEM to observe the phase evolution of LiCoO2 cathode material after 100 cycles, and found that LiCoO2 phase would degrade to Co3O4 phase. The phase transition of Co3O4 from LiCoO2 gave rise to lattice expansion, by which the anisotropic strain was proposed by first-principles calculation to inhibit LiCoO2 degradation. Results show that the anisotropic strain via the extension of lattice parameter
c
and the compression of
a
enables to simultaneously impede lattice oxygen loss and structure transition of LiCoO2 during delithiation at high voltage. In this case, the elongation of interplanar spacing also increases the diffusivity of Li ions in LiCoO2, contributing to rate performance.
MoO3-TeO2 glass system for gamma ray shielding applications
Authors: Al-Buriahi M S , Arslan Halil , Tekin H O , Singh V P , Tonguc Baris T
Published: January 2020

This paper examines the gamma-ray shielding features of some selected tellurite-based glasses in the form of xMoO3(100−x)TeO2 (20 ≤ x ≤ 50 mol%). Mass attenuation coefficients (μ

m
) of these glasses have been calculated using Geant4 toolkit and XCOM program for photon energy range of 1 keV—1000 MeV. The correlation factor (R2) between these two methods was found to be almost one. Shielding effectiveness for these glasses has been estimated by computing half value layer (HVL), effective atomic number (Z

eff
), and mean free paths (MFP). It was noticed that the heavy metal oxide of TeO2 plays an important role in improving the shielding effectiveness of the glasses. The Mo20Te80 glass has shown the promising properties to serve for gamma ray protection applications as compared with many conventional concretes and other newly developed glasses.
Design of high strength titanium alloy through finding a critical composition with ultra-fine α phase
Authors: Zhang Li-gang , Zhou Jing-ya , Wang Zhen-yu , Tang Jing-lu , Wu Di , Liu Li-bin
Published: January 2020

This study presents the design of a high strength titanium alloy based on the idea that the β titanium alloy with critically stable composition could precipitate ultra-fine α phase. An efficient method was used to find the composition of TC21-xV alloy in which ultra-fine α phase could be obtained. It is found that TC21-5V alloy containing ultra-fine α phase and possessing highest hardness could be obtained after solution treatment in the β single-phase region and subsequent aging. The morphology of primary and secondary α phases can be controlled by changing the solution treatment and aging temperatures. Calculation results of driving force and growth rate of secondary α phase show that the growth rate may be a decisive factor for the final size of secondary α phase after solution and aging treatments in the two-phase region. Finally, when the alloy was solution treated at 820 °C and aged at 500 °C, the highest strength of 1540 MPa was obtained. The alloy was solution treated at 820 °C and aged at 600 °C exhibited high strength of 1210 MPa with 11.4% elongation.
The Feature-Viewer: a visualization tool for positional annotations on a sequence
Authors: Paladin Lisanna , Schaeffer Mathieu , Gaudet Pascale , Zahn-Zabal Monique , Michel Pierre-André , Piovesan Damiano , Tosatto Silvio C E , Bairoch Amos
Published: January 2020

The Feature-Viewer is a lightweight library for the visualization of biological data mapped to a protein or nucleotide sequence. It is designed for ease of use while allowing for a full customization. The library is already used by several biological data resources and allows intuitive visual mapping of a full spectra of sequence features for different usages.

Availability and implementation

The Feature-Viewer is open source, compatible with state-of-the-art development technologies and responsive, also for mobile viewing. Documentation and usage examples are available online.
Digitization and the Future of Natural History Collections
Authors: Hedrick Brandon P , Heberling J Mason , Meineke Emily K , Turner Kathryn G , Grassa Christopher J , Park Daniel S , Kennedy Jonathan , Clarke Julia A , Cook Joseph A , Blackburn David C , Edwards Scott V , Davis Charles C
Published: January 2020

Natural history collections (NHCs) are the foundation of historical baselines for assessing anthropogenic impacts on biodiversity. Along these lines, the online mobilization of specimens via digitization—the conversion of specimen data into accessible digital content—has greatly expanded the use of NHC collections across a diversity of disciplines. We broaden the current vision of digitization (Digitization 1.0)—whereby specimens are digitized within NHCs—to include new approaches that rely on digitized products rather than the physical specimen (Digitization 2.0). Digitization 2.0 builds on the data, workflows, and infrastructure produced by Digitization 1.0 to create digital-only workflows that facilitate digitization, curation, and data links, thus returning value to physical specimens by creating new layers of annotation, empowering a global community, and developing automated approaches to advance biodiversity discovery and conservation. These efforts will transform large-scale biodiversity assessments to address fundamental questions including those pertaining to critical issues of global change.
Reporting Racist Hate Crime Victimization to the Police in the United States and the United Kingdom: A Cross-National Comparison
Authors: Myers Wesley , Lantz Brendan
Published: January 2020

Hate is a global phenomenon as evidenced by recent increases in hate crimes in both the United States and the United Kingdom; unfortunately, these crimes are also substantially underreported in both nations. Following this, this research presents an examination of racially motivated hate crimes and victim reporting to the police in both nations using data from the National Crime Victimization Survey and the Crime Survey of England and Wales from 2003 to 2015. Results indicate that, overall, victim reporting has been increasing in the United Kingdom and decreasing in the United States. Disaggregating by victim and offender race, however, reveals divergent trends such that anti-black hate crime victim reporting is increasing in the United States and decreasing in the United Kingdom. Policy and research implications are discussed.
Long-term post-mortem studies following neurturin gene therapy in patients with advanced Parkinson’s disease
Authors: Chu Yaping , Bartus Raymond T , Manfredsson Fredric P , Olanow C Warren , Kordower Jeffrey H
Published: January 2020

We performed post-mortem studies on two patients with advanced Parkinson’s disease 8 and10 years following AAV2-neurturin (CERE120) gene therapy, the longest post-mortem trophic factor gene therapy cases reported to date. CERE120 was delivered to the putamen bilaterally in one case (10 years post-surgery), and to the putamen plus the substantia nigra bilaterally in the second (8 years post-surgery). In both patients there was persistent, albeit limited, neurturin expression in the putamen covering ∼3–12% of the putamen. In the putamen, dense staining of tyrosine hydroxylase-positive fibres was observed in areas that contained detectable neurturin expression. In the substantia nigra, neurturin expression was detected in 9.8–18.95% and 22.02–39% of remaining melanin-containing neurons in the patient with putamenal and combined putamenal and nigral gene delivery, respectively. Melanized neurons displayed intense tyrosine hydroxylase and RET proto-oncogene expression in nigral neurons in the patient where CERE120 was directly delivered to the nigra. There was no difference in the degree of Lewy pathology in comparison to untreated control patients with Parkinson’s disease, and α-synuclein aggregates were detected in neurons that also stained for neurturin, RET, and tyrosine hydroxylase. These changes were not associated with antiparkinsonian benefits likely due to the limited neurturin expression. This study provides the longest term evidence of persistent transgene expression following gene delivery to the CNS and the first human results when targeting both the terminal fields in the putamen as well as the originating nigral neurons.
The ‘creatures’ of the human cortical somatosensory system
Authors: Saadon-Grosman Noam , Loewenstein Yonatan , Arzy Shahar
Published: January 2020

Penfield’s description of the ‘homunculus’, a ‘grotesque creature’ with large lips and hands and small trunk and legs depicting the representation of body-parts within the primary somatosensory cortex (S1), is one of the most prominent contributions to the neurosciences. Since then, numerous studies have identified additional body-parts representations outside of S1. Nevertheless, it has been implicitly assumed that S1’s homunculus is representative of the entire somatosensory cortex. Therefore, the distribution of body-parts representations in other brain regions, the property that gave Penfield’s homunculus its famous ‘grotesque’ appearance, has been overlooked. We used whole-body somatosensory stimulation, functional MRI and a new cortical parcellation to quantify the organization of the cortical somatosensory representation. Our analysis showed first, an extensive somatosensory response over the cortex; and second, that the proportional representation of body parts differs substantially between major neuroanatomical regions and from S1, with, for instance, much larger trunk representation at higher brain regions, potentially in relation to the regions’ functional specialization. These results extend Penfield’s initial findings to the higher level of somatosensory processing and suggest a major role for somatosensation in human cognition.
Community as contact zone: the power dynamics of community formation on a British council estate
Authors: Leaney Sarah
Published: January 2020

This paper explores the formation of ‘community’ on a British council estate as a process of negotiation enacted within a ‘contact zone’, a social space defined by a struggle between different cultural values within asymmetrical relations of power. Building on a discursive turn within theorizations of class, the paper explores the mobilization of discourses of community as a process of making class on The Estate. Based on ethnographic research, the paper offers an analysis of the field dynamics of the Community Centre, where community is enacted, negotiated, subverted and critiqued. This paper shows how a focus on the dynamic nature of discursive reproduction enacted in everyday negotiations within the ‘contact zone’ moves our understanding beyond structural accounts of class, incorporating agentic responses and everyday resistances into an analysis of the formation of class and community on The Estate.
Rhesus Macaque Brain Developmental Trajectory: A Longitudinal Analysis Using Tensor-Based Structural Morphometry and Diffusion Tensor Imaging
Authors: Kim Jeongchul , Jung Youngkyoo , Barcus Richard , Bachevalier Jocelyne H , Sanchez Mar M , Nader Michael A , Whitlow Christopher T
Published: January 2020

The typical developmental trajectory of brain structure among nonhuman primates (NHPs) remains poorly understood. In this study, we characterized the normative trajectory of developmental change among a cohort of rhesus monkeys (n = 28), ranging in age from 2 to 22 months, using structural MRI datasets that were longitudinally acquired every 3–4 months. We hypothesized that NHP-specific transient intracranial volume decreases reported during late infancy would be part of the typical developmental process, which is driven by volumetric contraction of gray matter in primary functional areas. To this end, we performed multiscale analyses from the whole brain to voxel level, characterizing regional heterogeneity, hemispheric asymmetry, and sexual dimorphism in developmental patterns. The longitudinal trajectory of brain development was explained by three different regional volumetric growth patterns (exponentially decreasing, undulating, and linearly increasing), which resulted in developmental brain volume curves with transient brain volumetric decreases. White matter (WM) fractional anisotropy increased with age, corresponding to WM volume increases, while mean diffusivity (MD) showed biphasic patterns. The longitudinal trajectory of brain development in young rhesus monkeys follows typical maturation patterns seen in humans, but regional volumetric and MD changes are more dynamic in rhesus monkeys compared with humans, with marked decreases followed by “rebound-like” increases.
Thin-layer Chromatography and Enzyme Immunoassay of L-Alpha-Acetyl Methadol and Methadone Metabolites in Urine
Authors: McIntyre Joyce A , Armandi Arlene E , Risen Lance P , Ling Walter , Haberfeldel George C
Published: January 2020

We describe a thin-layer chromatographic technique suitable for isolating at least four metabolites of L-α-acetyl methadol. The metabolites are discussed in terms of their color reactions to chromatography spray reagents and their appearance in the urine during various time intervals after dosage. Methadone is detected by the presence of the unmetabolized drug and two of its metabolites in the urine. We present a simple means of distinguishing methadone-containing specimens from those that contain L-α-acetyl methadol. Results of an immunoassay for methadone applied to specimens from patients receiving L-α-acetyl methadol or methadone are discussed. The method is suitable as a routine screening procedure for most laboratories that use thin-layer chromatography.
Simplified Automated Method for Determination of Urinary or Serum Uric Acid, Based on Reduction of Ferric-Phenanthroline Complex
Authors: Nelson John W , Batra K K
Published: January 2020

We describe an automated colorimetric method for determination of uric acid in serum or urine by use of an AutoAnalyzer II or SMA 12/60 (Technicon Corp.). The method depends on reduction of a ferric-phenanthroline complex by uric acid under acidic conditions to a ferrous-phenanthroline complex, which absorbs at 505 nm. Advantages of this method over other methods now in use are that color and concentration are linearly related (to 20 mg/100 ml); aqueous reagents are easily prepared, stable, and inexpensive; and interference from ascorbic acid has been eliminated by use of an alkaline copper-containing diluent. The analysis is also free of interference from glucose, creatinine, glutathione, salicylates and hemoglobin. Correlation with results of the Technicon phosphotungstic acid reduction method is excellent (r = .996). Correlation with results of an automated uricase method is satisfactory (r = .979). Recovery of uric acid was 101% over a wide concentration range.
Therapeutic and Toxic Concentrations of More than 100 Toxicologically Significant Drugs in Blood, Plasma, or Serum: A Tabulation
Authors: Baselt Randall C , Wright James A , Cravey Robert H
Published: January 2020

Human blood, plasma, or serum concentrations of drugs important to the analytical toxicologist are tabulated, as an aid to interpretation of analytical toxicological results. Significant pharmacological factors are included such as dosage, route and frequency of administration, number and weight of subjects, and time of sampling.
Evaluation of Discrepancies in Patients' Results— An Aspect of Computer-Assisted Quality Control
Authors: Whitehurst Philip , Di Silvio Thomas V , Boyadjian Gaydzag
Published: January 2020

A computer program has been devised to select those clinical chemistry results that have a high probability of error for inclusion on a discrepancy report, which is printed on demand throughout the day. Each report entry is evaluated by a supervisor, who decides whether to accept the result or to re-assay. With this program, 8.4% of all results were included on the report, 1.9% were re-assayed, and 0.83% were judged to be in error and corrected. Checking results at the time of their release to the computer has led to earlier report delivery and more convenient timing of re-assays without compromise of patient safety.
Modification of the Fiske and SubbaRow Method for Total Phospholipid in Serum
Authors: Naito Herbert K
Published: January 2020

Many of the difficulties encountered in the original Fiske and SubbaRow method for estimating serum phospholid were corrected through the use of vanadium pentoxide, a catalyst used in sample digestion, and through other minor modifications. Results obtained by the modified method agree well with those obtained by three other established phospholipid procedures. The greatly improved speed, simplicity, accuracy, and precision now makes the modified Fiske and SubbaRow method ideal for clinical or research use.
Ultraviolet Spectrophotometry of Theophylline in Plasma in the Presence of Barbiturates
Authors: Jatlow Peter
Published: January 2020

Ultraviolet spectrophotometry is widely used for the analysis of theophylline in blood, for purposes of monitoring therapy, and for pharmacokinetic studies. Phenobarbital, a component of common oral theophylline preparations, interferes with assays now in use. The modification of the method of Schack and Waxler [J. Pharmacol. Exp. Ther. 97, 283 (1949)] presented in this paper eliminates barbiturate interference. After solvent extraction and back extraction into NaOH, the pH of the alkaline solution is adjusted from pH 13 to 10 before spectrophotometric measurement. This shifts the barbiturate absorption maximum from 255 to 240 nm, permitting accurate analysis of theophylline, the spectrum of which is unaffected by the pH change.
Laboratory Diagnosis of Bence Jones Proteinuria in a Patient with Plasma Cell Leukemia
Authors: Chow Chiman , Spitzer Ralph W
Published: January 2020

Kappa Bence Jones proteinuria was found by immunoelectrophoretic techniques in a patient with plasma cell leukemia, who presented with no M-proteins either in serum or urine. However, a significant decrease in normal immunoglobulins was observed. On microscopic examination of kidney sections obtained at autopsy, protein casts were seen in the distal tubules. Bence Jones protein was not detected by the conventional heat test
Simplified Scatchard-Plot Assay for Estrogen Receptor in Human Breast Tumor
Authors: Johnson Roy B , Nakamura Robert M , Libby Rose Mary
Published: January 2020

In this two-point Scatchard-plot assay, with which a test of competitive inhibition is combined, the sample is mechanically homogenized in a buffer containing dithiothreitol, ultracentrifuged to obtain a fat-free cytosol, the protein content of which is then adjusted, and free and bound labeled estradiol are separated with dextrancoated charcoal after overnight incubation. We tested the method for precision and reliability by assaying such cytosols from pregnant rabbit uteri before and after dilution with kidney cytosol, and by assaying several other target and nontarget animal and human tissues. The Scatchard plot data were more reliable than tests for percent inhibition of binding by a competitor (diethylstilbestrol). For a tumor tissue to be judged positive it must bind at least 8 fmol of estradiol per milligram of protein and have a Kd of 0.1 to 5 x 10-10 mol/liter. Some nontarget tissues showed less than 70% inhibition by 104-fold concentrations (over labeled estradiol) of inhibitor. Of 19 breast-tumor specimens, seven were found to be positive.