Search

Plant proteins can provide advantages as a mechanism for disease modification to facilitate the management and treatment wherein seed proteins have ribosome inactivating, antitumor, immunomodulatory and abortifacient therapeutic properties. The present study investigates the antiproliferative activity of seed crude proteins from Mallotus philippensis against A549, SW480 and MCF-7 cell lines. M. philippensis seed (100 g) was extracted and obtained 640 g crude protein. SDS-PAGE analysis helped to identify 10 protein bands in the crude protein and its precipitation with ammonium sulphate increased its weight by 2.25-fold measuring 1440 µg and contained 12 protein bands ranging from 14 to 60 kDa wherein some bands were of huge intensity. MTT assay recorded decrease in cell viability with IC50 value of 4.18 ± 1.09 µg to A549, 4.21 ± 0.93 µg to SW480 and 8.99 ± 1.52 µg to MCF-7 cells. Seed crude protein did not exhibit cytotoxic activity in peripheral blood mononuclear cells but exhibited notable toxic effects against colon and lung cancer cells compared to breast cancer cells. AO/EtBr staining revealed morphological changes indicating fragmentation of nuclei, color of the nuclear chromatin and its degradation. Hoechst 33,258 staining showed apoptotic features of nuclear condensation, bright staining and fragmentation. The results conclude that M. philippensis seed protein possesses more potent antiproliferative activity against the tested cancer cell lines. At the outset, the positive results may open an avenue to identify a specific protein as anticancer drug in future.

The effect of temperature over the range of ambient to 704 °C and strain rate from 10−4 to 10−2 s−1 on the tensile properties and fracture behavior of ATI 718Plus was investigated. The results showed that with increase in temperature at a strain rate 10−4 s−1, there is a small reduction in the yield strength, but a large drop in ductility at 704 °C. This reduction was accompanied by a change in fracture mode from ductile transgranular to brittle intergranular cracking. Detailed analysis of the microstructure and microchemistry of the areas around the crack using electron microscopy showed that the driving mechanism behind the failure at elevated temperatures and slow strain rates is oxygen-induced intergranular cracking, a dynamic embrittlement mechanism. In addition, the results suggest that the δ precipitates on the grain boundaries tend to oxidize and may facilitate the oxygen-induced intergranular cracking. Finally, an increase in strain rate at 704 °C caused a small increase in the yield strength and a huge increase in ductility. This increase in ductility was accompanied by a change in fracture mode from brittle-to-ductile failure. Possible mechanisms for the deformation, failure mechanisms, and strain rate dependence are discussed.

Titanium dioxide-based systems are the preferred photo-catalytic materials. Among this the commercial P25 has been consistently employed for Photo-catalytic and PEC applications. This system ( ~20% Rutile and ~80% anatase) possibly crystallizes in a core shell configuration and the relevance of this. patterning for the observed photo-catalytic or Photo-electrochemical (PEC) activity is examined.

A deformation mechanism, rarely reported in Ti alloys, has been observed involving α/β interfacial and colony boundary sliding. This paper reports the initial characterization of this mechanism, involving a comparative study of the deformation behaviors of the new alloy (Ti–0.85Al–4.0V–0.25Fe–0.25Si–0.15O, in wt%) and an established α/β alloy. Both alloys exhibited slip steps on their surfaces. However, the new alloy may also deform by a mechanism which manifests itself as sliding at α/β interfaces and colony boundaries. This mechanism is consistent with the provision of significant ductility during very high strain rate testing, a property exhibited by the new alloy.

The US plan for high-level nuclear waste includes the immobilization of long-lived radionuclides in glass or ceramic waste forms in stainless-steel canisters for disposal in deep geological repositories. Here we report that, under simulated repository conditions, corrosion could be significantly accelerated at the interfaces of different barrier materials, which has not been considered in the current safety and performance assessment models. Severe localized corrosion was found at the interfaces between stainless steel and a model nuclear waste glass and between stainless steel and a ceramic waste form. The accelerated corrosion can be attributed to changes of solution chemistry and local acidity/alkalinity within a confined space, which significantly alter the corrosion of both the waste-form materials and the metallic canisters. The corrosion that is accelerated by the interface interaction between dissimilar materials could profoundly impact the service life of the nuclear waste packages, which, therefore, should be carefully considered when evaluating the performance of waste forms and their packages. Moreover, compatible barriers should be selected to further optimize the performance of the geological repository system. Immobilization of radionuclides in glass or ceramic forms in stainless steel in deep geological repositories is planned in the US for disposal of nuclear waste. Under simulated repository conditions, corrosion could be significantly accelerated at the interfaces of different barrier materials.

Using advanced aberration-corrected scanning transmission electron microscopy coupled with high-resolution energy-dispersive spectroscopy techniques, transitions to microstructure and composition occurring at a grain boundary (GB) crack-tip in Waspaloy after dwell-fatigue at 704 °C are characterized at the nano to atomic scale. The simple microstructure of this γ/γ′ superalloy, which enables elucidation of oxygen effect ahead of the oxide intrusion—dissolution of the precipitates fostering selective segregation of Al to the GB to form oxides—has been experimentally observed.

The development of high-temperature heavy-duty turbine disk materials is critical for improving the overall efficiency of combined cycle power plants. An alloy development strategy to this end involves superalloys strengthened by ‘compact’ γ′-γ″ coprecipitates. Compact morphology of coprecipitates consists of a cuboidal γ′ precipitate such that γ″ discs coat its six {001} faces. The present work is an attempt to investigate the microstructure and creep behavior of a fully aged alloy exhibiting compact coprecipitates. We conducted heat treatments, detailed microstructural characterization, and creep testing at 1200 °F (649 °C) on an IN718-variant alloy. Our results indicate that aged IN718-27 samples exhibit a relatively uniform distribution of compact coprecipitates, irrespective of the cooling rate. However, the alloy ruptured at low strains during creep tests at 1200 °F (649 °C). At 100 ksi (689 MPa) load, the alloy fails around 0.1% strain, and 75 ksi (517 MPa) loading causes rupture at 0.3% strain. We also report extensive intergranular failure in all the tested samples, which is attributed to cracking along grain boundary precipitates. The results suggest that while the compact coprecipitates are indeed thermally stable during thermomechanical processing, the microstructure of the alloy needs to be optimized for better creep strength and rupture life.

Titanium and titanium alloys are excellent candidates for aerospace applications owing to their high strength to weight ratio. Alpha/beta titanium alloys are used in nearly all sections of the aircraft, including the fuselage, landing gear, and wing. Ti-6Al-4V is the workhorse alloy of the titanium industry, comprising of nearly 60% of total titanium production. TIMETAL® 407, Ti-0.85Al-3.9V-0.25Si-0.25Fe (Ti-407) is an excellent candidate for alloy applications requiring excellent machinability and increased energy absorption. These properties are a result of the alloy’s increased ductility while maintaining moderate levels of strength. In this study, the deformation mechanisms of Ti-407 have been studied at high strain rates using split-Hopkinson bar testing. Utilizing post-mortem characterization, Ti-407 has been shown to deform significantly by ⟨c+a⟩ slip and deformation twinning. The observation of ⟨c+a⟩ slip is in contrast with other studies and will be discussed further.

This work investigates two nominally similar polycrystalline alloys, with a subtle difference in Nb content, intended to elucidate its effect on local phase transformation strengthening during high temperature creep. Tests were conducted at 750 °C and 600 MPa to target the creep regime dominated by superlattice intrinsic and extrinsic stacking faults, as well as microtwinning. Alloy A, with higher Nb and lower Al, was found to be superior in creep strength to Alloy B, with lower Nb and higher Al, as well as previously investigated ME3 and LSHR. Atomic resolution scanning transmission electron microscopy and energy-dispersive spectroscopy found that this increased creep strength was due to a novel local phase transformation occurring along microtwin boundary interfaces as a result of the Nb increase. Complementary density functional theory calculations helped to confirm that this was χ phase formation. It is hypothesized that this transformation was the cause of the increased creep strength exhibited by Alloy A.

The strength of a commercial β‑titanium alloy was tuned by systematically controlling the size-scale of α precipitation via two-step heat treatments. While the first step annealing at 350 °C forms the precursor metastable ω phase, the subsequent annealing at 600 °C/1H resulted in fine-scale α precipitation. We find that annealing duration at 350 °C greatly impacts the α size-scale and, this consequently can be used to tune the ultimate tensile strength (UTS) from ~1 to 2 GPa. A combination of high volume-fraction of non-shearable super-refined α precipitates, coupled with their pyramidal arrangement, and a constrained β matrix leads to very high strength.

Memecylon subcordatum (Melastomataceae) is an endemic and critically endangered species of the Kalakkad-Mundanthurai Tiger Reserve in India. Twenty five inter-simple sequence repeat primers were used to screen 86 individuals. Nine primers produced a total of 61 bands (6.77 bands primer−1) ranging from 200 to 1900 bp wherein 48 bands were of polymorphic. Polymorphism was 78.69% within the species, 26.60% within the populations and 7.41%–48.15% among the populations. Genetic variation varied from 0.3069 (within species) to 0.1182 (within populations). The poor gene flow among the populations (Nm: 0.3133) could be due to the genetic barriers caused by the tributaries of Tambraparani river. The coefficient of genetic differentiation between the populations (GST) was 0.6148. The Bayesian analysis, multidimensional scaling analysis and principal coordinates analysis grouped all the 11 populations under 4 clades. The Mantel test showed significant correlation between the matrices of genetic and geographic distances (r = 0.652, P

Due to the competing influences of configurational entropy and enthalpy of mixing, in recent years, secondary (including intermetallic) phases have been reported in many high entropy alloy (HEA) systems. These secondary phases offer great potential in terms of strengthening the HEA beyond the solid solution strengthening effects, and as such are of great interest in regards to alloy design for engineering applications. The present research investigates novel nano-scale core–shell precipitates forming within the disordered bcc matrix phase of an Al2CrCuFeNi2 HEA, utilizing complementary high-resolution microscopy techniques of atom probe tomography (APT) and transmission electron microscopy (TEM). The size, morphology, and local chemistry of these core–shell precipitates was measured by APT, and the composition was further corroborated by high-resolution scanning transmission electron microscopy–energy dispersive spectroscopy in an aberration-corrected TEM. Furthermore, high-resolution TEM imaging of the core–shell structure indicates that the Cu-rich core exhibits a bcc crystal structure.

The crystallography and structure of the interfaces formed between refined hexagonal close packed (hcp) α precipitates and the body centered cubic (bcc) β matrix in a solution-treated and quenched metastable β titanium alloy, Ti-5Al-5Mo-5V-3Cr (wt%, Ti-5553), were investigated after heating to 600 °C and subsequently aging for 0 and 30 min, respectively. The two phases adopted the classical Burgers orientation, and the observed interfacial structures were analyzed using a topological model, i.e. they contained disconnections, as well as β crystal lattice dislocations acting as a lattice invariant deformation (LID). The structure of the α/β interface was observed along two mutually perpendicular directions, in high angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). Viewed along the [ 0001 ] α : [ 110 ] β directions, an array of disconnections was observed to accommodate the misfit between the α and β crystals. While the spacing of these disconnections varied, the step height associated with them was always twice the { 112 } β interplanar spacing, and their Burgers vector b was [ − 0.019 0.019 0.034 ] β . When the interface was viewed along the [ 1 ¯ 1 ¯ 20 ] α : [ 1 ¯ 11 ] β direction, in the sample aged for 0 min at 600 °C the misfit between the two lattices along [ 0001 ] α : [ 110 ] β was so small that no misfit or lattice invariant dislocations were observed within the field of view, in contrast with the interface structure reported in other more conventional titanium alloys. After aging the sample for 30 min, however, the interfacial structure equilibrated, and crystal lattice dislocations were observed on the terrace planes, accommodating the LID, with b = 1 2 [ 1 ¯ 1 ¯ 1 ¯ ] β . Growth of the α precipitates is shown to occur principally by the emission of disconnections from the tip of the existing α precipitates into the β matrix, and its resulting conversion to α. These results, combined with analysis using the topological model, show that the nucleation and growth of the hcp α phase from the bcc β matrix in this alloy can be described in terms of the motion of disconnections, accompanied by the displacive diffusion necessary to accommodate the differences in composition between the α and β phases.

In this work an optical reversible bistate joint NIMPLY (BJN) logic gate was designed using two-dimensional photonic crystals. The gate was designed using an asymmetrical waveguide with reference to a point defect introduced at the center of the structure. The desired logic functions were obtained in the forward and reverse state using the principle of interference of light. The defect rod radius and length of the waveguide using a line defect were chosen to introduce constructive and destructive interference of light. The BJN gate has a low footprint of 40.83 µm2 and the resonant wavelength was designed to be 1550 nm. The finite-difference time-domain method was used to attain the wave propagation and photonic bandgap for the proposed structure. The maximum contrast ratio of the reversible optical BJN gate in the forward and reverse states was found to be 25.11 dB and 24.86 dB, respectively.

Recently, a class of refractory high-entropy alloys has been developed with a refined microstructure consisting of an ordered B2 matrix with cuboidal BCC precipitates resembling an “inverted superalloy-like” microstructure. In this paper, we have studied the evolution of the duplex microstructure of AlMo0.5NbTa0.5TiZr during aging at elevated temperatures, particularly with regard to the nature of the B2 and BCC phases. Samples were aged at 1000 °C for 6 h, followed by a water quench. It was found that while the relative volume fractions of the B2 and BCC phases remained nearly constant after ageing, compositional changes of both the B2 and BCC phases were determined. In the aged condition, there is evidence from high-resolution STEM HAADF imaging that suggests that the B2 phase in the aged condition may undergo a spinodal reaction, with the sub-lattice occupancies differing within the ordered precipitates. A change in size and shape of the BCC precipitates was also noted, and this was accompanied by a difference in the nature of the B2/BCC interfaces. Thus, a step-like B2/BCC interface is evidenced in the aged condition, in contrast with the planar {100} interfaces in the “superalloy-like” microstructure, likely adopted to accommodate a change in coherency resulting from an increase in misfit between the two phases from compositional changes occurring during the coarsening of the BCC precipitates.

Novel imaging strategies in the scanning electron microscope aimed at significantly improved image contrast of second phases in metal alloys are described. These include the use of low accelerating voltages, small working distances, and a novel detection system. Contrast is assessed as a function of voltage and optimized imaging conditions which result in much improved image quality are presented. These strategies are applied to two precipitation hardened Ni-base alloys, a cast single crystal and a hot isostatically pressed sample.

Hydrogen embrittlement behavior of four heats of alloy 725 (H1, H2, H3, and H4) were characterized by measuring the crack growth rate response over a range of cathodic potentials. Significant grain boundary precipitation in two heats (H1 and H3) may have contributed to higher susceptibility, as evidenced by higher values of crack growth rate. The crack growth rate increased with increasing twin fraction. The crack morphology exhibited evidence of intergranular as well as slip band cracking. The crack growth rate response of the two heats that were less susceptible (H2 and H4) were evaluated in more detail over a range of applied potentials and stress intensity factors. Evidence of nano void formation at the intersection of dislocation slip bands, and grain boundaries suggests that hydrogen stabilized vacancies may play a role in the crack growth mechanism. Crack growth rate exhibited a strong response with applied potential varying by as much as 100 times in the potential range of −1050mV SCE to −850mV SCE. Over the range of K values evaluated, the crack growth rate increased by a factor of 3to 30 with applied K depending on the applied potential. The crack growth rate was related to the water adsorption on fresh metal surfaces of alloy 725 in the anticipated crack tip conditions. A crack tip strain rate based approach was applied to model the measured crack growth response.

The present study was designed to establish scientific evidence for the traditional claim on the use of fern Cyclosorus parasiticus in the treatment of rheumatism (inflammatory disease). Anti-inflammatory activity of the acetone extract of epidermal glands was tested by two models, viz., carrageenan and egg albumin-induced hind paw oedema. Before that, acute toxicity was performed following the OECD guidelines. No mortality was observed in experimental animals to the acetone extract at the test dose of 2000 mg/kg b.w. p.o. There were no signs and symptoms of toxicities. Hence, the extract was considered to be safe. The acetone extract of the epidermal glands showed dose-dependent activity against the development of oedema in experimental rats compared to the standards. The acetone extract significantly reduced the paw volume (*P

In a recent report of the ACS publications, there was a question on what is the most important unresolved problems in chemistry? The answer can be varied depending on the specialization one tends t...

This paper examines the essential ethos of classic values. There are many human values such as cultural, moral, spiritual and ethical values which are following by the Indians. It has been practicing from the traditional sanctity to the modern vicinity of life. The focus is the analysis of homogeneous of family dynamics and heterogeneous of cultural values in Upamanyu Chatterjee‘s The Last Burden and Way to Go. There is humongous information which can be excavated in Chatterjee‘s novels. He presents the myriad interconnection of family and culture in India. His novels seem to celebrate the cultural values which are attached to the Joint family system. Chatterjee portrays that the love of the family and culture is never ending through the character of dying Urmila and missing Shyamanand. His novels teach a lesson to other writers in the world how family as the major theme is treated in the literary works by the Indian writers. At the same time, his novels deal with the representation of Indian culture. The main objective of the paper is to delineate the multidimensional perspectives of family and cultural values in India. It describes theoretically and empirically through the narration of Jamun‘s family.

Objective: The term “wound” is defined as a disruption of normal anatomical structure. Therefore, “healing” is the complex and dynamic process that results in the restoration of anatomical continuity and function. Methods: Albino Wistar rats (150-180 g) of both sexes were selected. The experiment of Wound Healing Activity by Excision Wound Model and Incision Wound Model by the simple ointment B.P., reference standard drug (0.2% w/w nitrofurazone ointment), stigmasterol ointment (0.2% w/w), hexane, chloroform and methanol extract ointments of 3%, 4% and 5% w/w of leaves in Jatropha tanjorensis in simple ointment base (where 3g, 4g and 5 g of the extracts was incorporated in 100 g of simple ointment separately). Results: The time for wound closure to methanol extract ointment (5% w/w) and stigmasterol (0.2% w/w) was similar to that of standard drug, nitrofurazone ointment (0.2% w/w) 16±2 days in Excision Wound Model. The significant tensile strength at 3%: 4%: 5% w/w methanol extract ointments (p

A dissimilar weld between a low alloy steel (LAS) butter weld joined to a F65 steel pipe using a narrow groove hot wire gas tungsten arc welding (HW-GTAW) procedure with Alloy 625 filler metal was investigated. The weld interpass microstructure is comprised of large swirls formed by a macrosegregation mechanism involving partial, non-uniform mixing of liquid base metal with the lower melting temperature weld pool, followed by fast solidification. This mechanism produces steep gradients in composition and solidification behavior. The resulting swirls are composed of alternating iron-rich peninsulas and partially mixed zones (PMXZ) that are surrounded by planar and cellular zones exhibiting multiple solidification directions. Large austenitic grains, encompassing planar, cellular, and dendritic morphologies, nucleate off peninsulas in direct contact with the weld pool. The highest hardness was found in nickel and chromium rich PMXZs that exhibited a lath martensite microstructure. In the event of exposure to hydrogen containing environments, the PMXZs could serve as nucleation sites for hydrogen assisted cracking.

In this study, we applied a series of surface analysis techniques to explore the structure and chemistry of the corrosion products built up at the interface of different materials, which is relevant to the permanent disposal of world-wide high-level nuclear waste. Metallic alloys, amorphous glass, and crystalline ceramics are typical candidate nuclear waste forms planned for immobilizing and isolating the dangerous radionuclides enriched in the waste. The near-field corrosion interactions between these dissimilar materials are the focus of this study. The experiments were performed by corroding metallic alloys in intimate proximity to glass or ceramics in Cl--containing solutions at 90 oC. The exposed materials were subsequently subjected to comprehensive surface characterization using X-ray photoelectron spectroscopy, scanning transmission electron microscopy, energy dispersive spectroscopy, time-of-flight secondary ion mass spectrometry, and Raman/infrared spectroscopy analysis. The systematic study revealed localized damage on the alloy surface due to crevice corrosion. Interestingly, localized corrosion was also identified on the surface of some glasses and ceramics that were present nearby, while an inhibition effect was observed in other systems. These interactions were found to strongly depend on the type of materials and environment, which led to different corrosion phenomena.

To reduce self-corrosion of Al-Zn-In pigments in an Al-rich primer, trivalent chromium process (TCP) was applied to the pigments before mixing in the epoxy binder. The formation of TCP and its effects on both the Al-Zn-In bulk alloy and pigment particles were investigated in this study. The TCP layer on the Al-Zn-In alloy has a bilayer structure similar to TCP layers formed on other alloys. The corrosion rate of bulk Al-Zn-In alloy is reduced by the TCP treatment. The TCP layer likely blocks the access of Cl- to the Al-Zn-In alloy, which reduces corrosion attack initiation.

Embossed parts, that contain a number of features, are desired for a range of components, such as, heat exchangers, bipolar plates, micro-reactors, and micro-fluidics. A comparison of low strain rate embossing and high strain rate embossing was investigated in this study. High strain rate deformation at the embossed surface induced quatitatively different properties than those on a quasi-statically formed part. A commercial hand file was chosen as a simple and available die surface due to its high hardness and relatively fine features. Commercially pure copper (110) was embossed using four methods: quasi-static (static, low strain rate), magnetic pulse (MP, high strain rate), direct vaporizing foil actuator (direct VFA, high strain rate), and urethane-assisted vaporizing foil actuator (urethane VFA, high strain rate). Embossed depth, mechanical properties, and microstructure evolution were studied for both low strain rate embossing and high strain rate embossing. The results showed that generally better conformity to the die features and higher surface hardness were achieved with high strain rate embossing, in part because higher pressures could be developed with these methods. The study of the microstructure revealed that besides the grain size and shape change, significant twinning appeared along the deformed surface in high strain rate embossed parts. Optical microscopy (OM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were performed to study the resultant microstructure.

The compositional and order-disorder transition widths of γ′/γ interfaces in a Co–Al–W alloy have been established for the first time by coupling of aberration corrected high resolution scanning transmission electron microscopy and orientation-specific atom probe tomography. While the compositional width is approximately 2.5 nm, the order-disorder transition width is very sharp measuring 0.5 nm. A comparative study revealed that the γ′/γ interfaces, in a model Ni–Al–Cr alloy, are both compositionally and structurally diffuse with nearly the same width (~ 2.5–3 nm). These differences between the γ′/γ interfaces in Co and Ni-base alloys can impact the coarsening behavior of the ordered precipitates.