Effect of illite on the mechanical properties of subgrade soil under varying surcharge loads.

Due to its non-expanding properties, presence of Illite mineral in subgrade soil is investigated particularly on California bearing ratio (CBR), resilient modulus (MR) and swell potential. Multiple samples of stiff and weak subgrade soils with varying illite percentages were tested under six different surcharge loads ranging from 2.27 to 13.8 kg. Mineralogical analysis is performed using X-ray diffractometer and MR of soil is assessed using Ultrasonic pulse velocity (UPV) technique. Results showed a positive correlation between Illite percentage and both CBR and MR value. The soil with higher Illite content tends to exhibit higher CBR and MR values while those with higher montmorillonite content show lower values even with more Illite content. The CBR and MR values increases from 8.4% to 19 % and 139 MPa-315 MPa for stiff soil and 3.8%-11.7 % and 23 MPa-83 MPa for weak soil, respectively when the surcharge load was increase from to 2.27-13.8 kg. Additionally, a decrease in swell potential was observed from 1.64% to 1.09 % for stiff soil and 1.39%-0.84 % for weak soil with an increase in Illite percentage. The study also developed an improved relationship for predicting resilient modulus based on CBR value, showing a strong correlation with equations developed by many researchers in the past.

Open air X-ray diffractometer for crystallography, compression, contraction, and structural phase transitions with variable temperature capabilities.

It is a fact that materials contract or expand by changing their temperature. In a certain temperature range, the distance between atoms changes linearly in some materials whereas it changes non-linearly in other materials. X-ray diffraction (XRD) is one of the popular techniques used for understanding the crystal structure of these materials. However, XRD is mostly carried in open air at room temperature or require very expensive high vacuum set-ups and expensive temperature controllers for low temperature studies. Here we propose a design of a variable temperature X-ray diffractometer that can operate in dual modes: heating and cooling in open air. The proposed diffractometer has been used for studying structural phase transition in chromium nitride thin films. The results demonstrated not only the effectiveness of our proposed setup but also its applicability in advancing our understanding of complex material behaviors.•A new design of a variable temperature X-ray diffractometer has been introduced in this paper, which can be used for acquiring XRD data while heating or cooling samples in open air.•As a proof of concept, the newly designed variable temperature X-ray diffractometer is used for studying structural phase transition in CrN thin films.

Coating-thickness-dependent physical properties and cutting temperature for cutting Inconel 718 with TiAlN coated tools.

Introduction: Coating-thickness-dependent physical properties can induce different cutting temperatures with physical vapor deposition (PVD) titanium aluminum nitride (TiAlN) ceramic-coated tools. The determination of the optimal TiAlN coating thickness is important to obtain superior coating physical properties and decrease the cutting temperature of Inconel 718 alloy. Objectives: The present study investigates the effects of coating thickness on the physical properties of TiAlN coatings and the cutting temperature during the machining of Inconel 718 alloy. The optimal coating thickness is also determined. Methods: First, the direct-current-arc method was utilized to deposit PVD Ti0.55Al0.45N coatings with thickness of 1.6 µm, 2 µm, 2.5 µm, and 3 µm, onto a cemented carbide substrate. Second, the coating-thickness-dependent physical properties were characterized and estimated with a radar chart. Third, the effects of coating thickness on coating antifriction were analyzed with the tool-chip friction coefficient when cutting Inconel 718 with PVD TiAlN coated tools. Both the maximum cutting temperature generated in the chip and the cutting temperature of the tool bodies were measured for analyzation of the thermal barrier effect of coating. Finally, the topographies of the deformed chip and tool-chip contact area were obtained and investigated to determine the effects of coating thickness on the cutting temperature. Results: The tool-chip friction coefficient and coating thermal barrier effect were affected by the coating thickness. Ti0.55Al0.45N coated tools with moderate coating thickness had fine antifriction effect with Inconel 718. The thermal barrier effect of Ti0.55Al0.45N coating was positively related to the coating thickness. Conclusions: The optimal TiAlN coating thickness was determined as 2 µm, which resulted in superior physical properties and reduced the cutting temperature of Inconel 718.

Mechanism of Pyrolysis Reaction of Al-Rich Al/PTFE/TiH2 Active Material.

In order to obtain the chemical reaction mechanism of Al-rich Al/PTFE/TiH2 composites in argon and oxygen atmosphere, Al/PTFE, PTFE/TiH2, Al/TiH2 and Al-rich Al/PTFE/TiH2 with different contents of TiH2 composites were prepared by using the wet mixing method. The pyrolysis behavior of the above composites was investigated by thermogravimetric differential scanning calorimeter (TG-DSC). In addition, the calorific value of the above composite was measured by an oxygen bomb calorimeter. The compositions of TG-DSC residues at different peak temperatures and 1000 °C and the residues of oxygen bomb experiment were analyzed by X-ray diffraction (XRD), The results show that the pyrolytic products of Al-rich Al/PTFE/TiH2 materials under argon atmosphere can be divided into four stages. In the first stage (328.6-378.6 °C), the products are TiH1.924, (C2F4)n, (CF2)n, H2(g), Al and TiH2; in the second stage (510.8-534.3 °C), the products are Al, TiH1.924, (C2F4)n, (CF2)n, Ti, AlF3, TiF3, TiF4(g), C and H2(g). In the third stage (540.8-618.1 °C), the products are Al, C, Ti, (C2F4)n, (CF2)n, AlF3, TiF3, TiF4, CF4(g), C3F6(g), C4F8(g), C2F6(g), Al5Ti2 and H2(g); in the fourth stage (918.5-1000 °C), the products are AlCTi2, Al2Ti, AlTi, TiC, AlF3, Al, TiF3, TiC0.957, TiC0.981 and TiC0.95. The calorific value of the combustion of Al-rich Al/PTFE/TiH2 composite with 10% the content of TiH2 is the highest and is 19,899 J/g, which is 3.776% higher than that of Al-rich Al/PTFE composite. When TiH2 content is greater than zero and not more than 10%, the chemical reaction mechanism of Al-rich Al/PTFE/TiH2 is almost the same under oxygen atmosphere. When the content of TiH2 is higher than 10%, the mechanism of this material is different.

Low magnetic field promotes recombinant human BMP-2-induced bone formation and influences orientation of trabeculae and bone marrow-derived stromal cells.

Effects of high magnetic fields [MFs, ≥ 1 T (T)] on osteoblastic differentiation and the orientation of cells or matrix proteins have been reported. However, the effect of low MFs (< 1 T) on the orientation of bone formation is not well known. This study was performed to verify the effects of low MFs on osteoblastic differentiation, bone formation, and orientation of both cells and newly formed bone. An apparatus was prepared with two magnets (190 mT) aligned in parallel to generate a parallel MF. In vitro, bone marrow-derived stromal cells of rats were used to assess the effects of low MFs on cell orientation, osteoblastic differentiation, and mineralization. A bone morphogenetic protein (BMP)-2-induced ectopic bone model was used to elucidate the effect of low MFs on microstructural indices, trabecula orientation, and the apatite c-axis orientation of newly formed bone. Low MFs resulted in an increased ratio of cells oriented perpendicular to the direction of the MF and promoted osteoblastic differentiation in vitro. Moreover, in vivo analysis demonstrated that low MFs promoted bone formation and changed the orientation of trabeculae and apatite crystal in a direction perpendicular to the MF. These changes led to an increase in the mechanical strength of rhBMP-2-induced bone. These results suggest that the application of low MFs has potential to facilitate the regeneration of bone with sufficient mechanical strength by controlling the orientation of newly formed bone.

Copper nanoparticles: Green synthesis and managing fruit rot disease of chilli caused by Colletotrichum capsici.

The present study was focused on synthesis and characterization of copper nanoparticles to evaluate their efficacy against fruit rot pathogen of chilli crop. The green synthesis of nanoparticles was carried out by using extracts of Eucalyptus and Mint leaves. The synthesis of copper nanoparticles was confirmed by XRD, PSA, SEM and TEM. The average size of these particles synthesized by Eucalyptus leaf extract (CuNP-E) ranged from 10 to 130 nm, while as size of Mint leaf extract synthesized particles (CuNP-M) ranged from 23 to 39 nm, thus confirming their nano size. These green synthesized copper nanoparticles were evaluated against Colletotrichum capsici where Carbendazim 50 WP @ 500 ppm and copper oxychloride 50 WP @ 2500 ppm served as standard checks. The mycelia inhibition of Colletotrichum capsici caused by copper nanoparticles was studied on PDA medium. CuNP-M @ 1000 ppm showed highest mycelial inhibition of 99.78% followed by 93.75% at 500 ppm and CuNP-E @ 1000 ppm compared to standard fungicides, carbendazim 50 WP @ 500 ppm (72.82%), and copper oxychloride 50 WP @ 2500 ppm (85.85%). The CuNP-M @ 500 ppm were significantly superior to carbendazim 50 WP @ 500 ppm and copper oxychloride 50 WP @ 2500 ppm, but was statistically at par with CuNP-E @ 1000 ppm. This shows effectiveness of much lower concentration of copper nanoparticles compared to conventional fungicides. In detached fruit method, nanoparticles applied before inoculation of pathogen showed better results with regard to incubation period, lesion number and lesion size than after inoculation of pathogen. The present study reveals a simple, convenient, non-toxic and cost-efficient technique for the synthesis of nanoparticles and their effectiveness against Colletotrichum capsici. CuNP-M first time synthesized and evaluated against Colletotrichum capsici performed better than CuNP-E.

Dataset on microstructural, structural and tribology characterization of TiC thin film on CpTi substrate grown by RF magnetron sputtering.

The datasets in this article are supplementary to the corresponding research article [1, 2]. The planar morphology and topography of TiC thin films coated on commercially pure Titanium (CpTi) grown by RF magnetron sputtering were investigated using Field emission scanning electron microscope (FESEM) and Atomic force microscope (AFM). The mechanical properties such as Hardness and Young Modulus of the thin film coating was studied using Nanohardness. Furthermore, grazing incidence X-ray diffractometer (GIXRD) and Raman spectroscopy were used to analyse the structural and composition of the TiC thin film coating.

Lead ethyl dithiocarbamates: efficient single-source precursors to PbS nanocubes.

Lead ethyl dithiocarbamates have been successfully used as single-source precursors for the deposition of PbS using spin coating followed by annealing at moderate temperatures. The thin films were characterized using a powder X-ray diffractometer and were found to be face-centred cubic with the (200) plane being the most preferred orientation. Scanning electron microscopy images showed the formation of well-defined cubes. Optical band gaps of PbS thin films were estimated using Tauc plots as 0.72, 0.73 and 0.77 eV at annealing temperatures of 250, 300 and 400°C. These band gaps were all blue shifted from the bulk value of 0.41 eV. Energy-dispersive X-ray analysis was used to determine the composition of the thin films which showed an approximately 1 : 1 Pb to S ratio.

Magnetic ZnFe2O4 nanotubes for dispersive micro solid-phase extraction of trace rare earth elements prior to their determination by ICP-MS.

Magnetic ZnFe2O4 nanotubes (ZFONTs) with numerous pores on their walls were synthesized and characterized. They are shown to be a viable sorbent for dispersive micro-solid phase extraction of the trivalent ions of rare earth elements (REEs), specifically of lanthanum, praseodymium, europium, gadolinium, holmium and ytterbium. The specific surface area of ZFONTs is large (57 m2⋅g-1) and much bigger than that of ZnFeO4 nanoparticles (16 m2⋅g-1). It is shown that REEs are quantitatively retained on ZFONTs in the pH range of 7.0-9.0. The separation of the sorbent from the aqueous phase was achieved by an external magnetic field. Following elution with 0.5 mol⋅L-1 HNO3, REEs were quantified by inductively coupled plasma mass spectrometry. The main parameters influencing preconcentration and determination of the REEs were studied. Under optimum conditions, detection limits for REEs range from 0.01 (Ho) to 0.75 (La) pg⋅mL-1. Relative standard deviations are less than 6.5% (for n = 9; at 1.0 ng⋅mL-1). The method was applied to the determination of trace REEs in spiked biological and environmental samples and gave satisfactory results. Graphical abstract Schematic presentation of a new adsorbent for dispersive micro-solid phase extraction (DMSPE) combined with ICP-MS. Magnetic ZnFe2O4 nanotubes with many pores on their walls were used for preconcentration and determination of rare earth elements (REEs) in environmental and biological samples.

Forming Quality Analysis on the Cold Roll Forming C-channel Steel.

Cold roll forming, as a metal plastic forming process, is still mainly used in industrial production by the trial-and-error method, which wastes a lot of time and materials. In this paper, the C-channel steel is taken as the research object. First, the empirical equations of forming passes are verified and analyzed, then the cold roll forming model of C-channel steel is established, the forming quality of each pass and the stress-strain distribution of the whole sheet metal are analyzed, and the validity of the model is verified by experiments. The residual stresses of the web zone and flange of the finished product were measured. The results show that the empirical formulas are still not universal and the forming quality of the bite zone is poor. It needs to be adjusted by improving the distribution of deformation. The external surface of the C-channel steel is undertensile stress, while the internal surface is undercompressive stress, and the residual stresses of the flange are far greater than those of the web zone. The research provides a reference for the design of the bite zone and the number of forming passes.

Crystallographic home-source X-ray data for the atomic-resolution experimental phasing of the Shank3 SH3 domain structure from pseudomerohedrally twinned crystals.

By far most macromolecular crystallographic data collection and experimental phasing is nowadays carried out using synchrotron radiation. Here, we present two crystallographic datasets collected on a home-source X-ray diffractometer, which can per se be use to experimentally solve the atomic-resolution crystal structure of the Src homology 3(SH3)-like domain from the postsynaptic protein Shank3. The refined structure was described in the article "Structure of an unconventional SH3 domain from the postsynaptic density protein Shank3 at ultrahigh resolution" (Ponna et al., 2017) [1]. Crystals of the Shank3 SH3 domain were derivatized through soaking in 1 M sodium iodide prior to diffraction data collection at a wavelength of 1.54 Å. High-resolution data are reported for a native crystal to 1.01 Šand an iodide-derivatized one to 1.60 Å. The crystals suffered from several anomalies affecting experimental phasing: a high fraction (34-40%) of pseudomerohedral twinning, significant pseudotranslational symmetry (> 15%) with the operator 0.5,0,0.5, and a low solvent content. Twinning with the operator h,-k,-l is made possible by the space group P21 coupled with a unit cell ß angle of 90.0°. The data can be used to repeat and optimize derivatization and phasing procedures, to understand halide interactions with protein surfaces, to promote the use of home X-ray sources for protein structure determination, as well as for educational purposes and protocol development.

Research progress and strategy on identification and quality evaluation of animal-derived medicinal materials / 中草药

Animal-derived medicinal materials as the integral part play an extremely important role in the application of Chinese material medica (CMM), which are considered to have the advantages of strong activity, great potential, and wide applications. With the increasing demands for animal-derived medicinal materials, a large number of counterfeit, inferior, and confusing products have appeared in the market, which has seriously affected the use and quality evaluation of animal-derived medicinal materials. At the same time, the research development on identification and quality evaluation of animal-derived medicinal materials is slower than that of plant-derived medicinal materials, and the system is weak, especially lacking of characteristic and exclusive identification index and evaluation means. Therefore, how to establish and perfect the quality evaluation system of animal-derived medicinal materials is particularly important and will become the focus and hot work in the future. In this paper, the research progress of animal-derived medicinal materials identification and quality evaluation methods is summarized, and the problems and challenges in constructing its quality evaluation system are analyzed, so as to provide reference and new ideas for the establishment and improvement of animal medicine quality evaluation system.

Crystallographic orientation of the c-axis of biological apatite as a new index of the quality of subchondral bone in knee joint osteoarthritis.

The aim of the present study was to investigate the preferred orientation of biological apatite (BAp) as a new index of the quality of subchondral bone (SB) in knee joint osteoarthritis (OA). Ten OA and five normal knee joints were obtained. Thickness, quantity and bone mineral density (BMD) of SB were analyzed at the medial condyle of the femur in dry conditions by peripheral quantitative computed tomography. In addition, the preferred crystallographic orientation of the c-axis of BAp was evaluated as bone quality parameter using a microbeam X-ray diffractometer technique. BMD and thickness of SB were significantly increased in OA specimens compared to normal knee specimens (P < 0.01), and the preferred orientation of the c-axis of BAp along the normal direction of SB surface was significantly higher in OA specimens (P < 0.01), reflecting the change in stress of concentration in the pathological portion without cartilage. SB sclerosis in OA results in both proliferation of bone tissues and enhanced degree of preferential alignment of the c-axis of BAp. Our findings could have major implications for the diagnosis of clinical studies, including pathologic elucidation in OA.

A novel X-ray diffractometer for studies of liquid-liquid interfaces.

The study of liquid-liquid interfaces with X-ray scattering methods requires special instrumental considerations. A dedicated liquid surface diffractometer employing a tilting double-crystal monochromator in Bragg geometry has been designed. This diffractometer allows reflectivity and grazing-incidence scattering measurements of an immobile mechanically completely decoupled liquid sample, providing high mechanical stability. The available energy range is from 6.4 to 29.4 keV, covering many important absorption edges. The instrument provides access in momentum space out to 2.54 Å(-1) in the surface normal and out to 14.8 Å(-1) in the in-plane direction at 29.4 keV. Owing to its modular design the diffractometer is also suitable for heavy apparatus such as vacuum chambers. The instrument performance is described and examples of X-ray reflectivity studies performed under in situ electrochemical control and on biochemical model systems are given.

Crystallographic Texture in Ceramics and Metals.

Preferred crystallographic orientation, or texture, occurs almost universally, both in natural and man-made systems. Many components and devices in electronic and magnetic systems are fabricated from materials that have crystallographic texture. With the rapidly increasing use of thin film technology, where sharp axisymmetric crystallographic texture normal to the film plane is frequently observed, the occurrence and impact of texture are rising. Thin film applications in which the texture of the material plays a key role in determining properties and performance are broad: complex oxides in random access memory devices, ZnO thin film resonators for cell phone applications, metallic alloys in magnetic recording media, and Al and Cu interconnects in integrated circuits are but a few examples. Texture is established during the synthesis or post-synthesis heat treatment of a material and thus has a strong dependence upon processing history. Accurate measurement of texture is not simple and a variety of tools and approaches are being actively employed in texture studies. X-ray, neutron and electron diffraction based techniques are practiced around the world at varying levels of complexity with regard to equipment and analysis methods. Despite the well-documented existence of these varied approaches, many reported texture measurements on electronic materials are based solely on the relative intensities of conventional θ-2θ x-ray diffraction peaks, which typically yield inaccurate results. NIST has developed quantitative texture measurement techniques that employ equipment commonly available in most industrial and academic settings. A number of examples of texture measurement in ceramic and metal systems will be presented, taken from the historical development and application of these techniques at NIST over the past 7 years.