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The study was focused on investigating the spray and droplet characteristics of spiral and flat-fan nozzles computationally. The Spiral nozzle and the flat-fan nozzle are generally used in fire suppression application. The computational analysis had been carried out in ANSYS. The nozzle parameters like spray pattern, spray flow rate, impact, weber number were examined at different pressures say 1 bar to 3 bar. During this study the volume fraction of air and water were maintained equally. The spray pattern of spiral nozzle is not uniform and the droplets produced from the spray are coarse. The flat-fan nozzle produces a solid-cone pattern spray with oval impact area with a width of approximately ½ of its length. The flat-fan nozzle has higher spray flow rates and higher sprays impact than the spiral nozzles. The spiral nozzle acquires the maximum spray angle and the minimum droplet size and hence it is considered as highly efficient spray nozzle.

The main objective of this research is to provide better controlling and stability to B767 aircraft, where a study of elevators for pitch control for the described longitudinal movement is conducted. Intelligent controllers are designed and introduced to the surfaces of the linearized model of B767 aircraft, to identify the performance level based on time response and stability analysis by using different transfer functions. Self-tuning PID Controller and designed hybrid intelligent controller with a combination of PID controller and fuzzy controller are proposed along with few sensors installation to obtain results. A comparative assessment and quantitative analysis of controllers are carried out using MATLAB Simulink. This research has shown that the performance of the aircraft has improved significantly.

Water is a renewable resource for the Sustaining Ecosystem. Rapid industrialization and population impacts the climate. The imbalance of Climate changes over various geographical regions affects the hydrological and morphological behaviour of water resources. The Water balances of the system are analysed via the SWAT Model (Soil and Water Assessment Tool). By simulating and predicting future hydrological behaviour with different scenarios using many climatological models. Using weather data and predicting future hydrological outputs such as Runoff, Temperature, Base flow, groundwater flow, AET etc. in 21st century. Model is calibrated and validated using statistical methods. Results of various modelling Researches in field of SWAT and their major findings are discussed in this review paper. The future Scope of SWAT modelling and its Applications are also recommended. Forty papers are discussed in tabular form with their results and their future improvements were concluded. This paper fulfills a need for precise and quick reviews of recent researches in field of SWAT modelling with climate change on water resources. This will help researchers, academician’s insights into precise climate change impacts on water resources in 21st Century. Necessary steps to be adopted for their successful extreme repercussions of climate change and measures adopted for managing the severe damages to our Ecosystem with sustainable development goals in new millennium are discussed.

Aim: The present study aimed to synthesize and characterize carbon nanoparticles (CNPs) from a new precursor and to evaluate its effect on the viability of healthy seeds and cell lines. Methodology: The CNPs were synthesized by acid assisted carbonization of carbohydrate and its characteristics such as size, fluorescence property and purity of samples were evaluated for confirmation. Cytotoxic studies were performed in MCF 10a cell lines using 3-4,5-dimethylthiazol-2,5-diphenyltetrazolium bromide (MTT) assay whereas the phytotoxic assay was conducted by using scallions and Indian pearl millet. Results: Transmission electron microscope (TEM) results showed that nano-sized CNPs [10-40 nm] were synthesized and its characteristic peaks were observed in Ultraviolet (UV) and fluorescence spectrum. The Energy Dispersive X-ray (EDAX) analysis confirmed the presence of carbon and oxygen without any impurities. It was non-cytotoxic for healthy MCF 10a cell lines and did not affect the germination rate of Indian pearl millets at higher concentrations. In both toxicity studies, the viability of cells and plants was >95% even after exposure to a high concentration of CNPs. Interpretation: The non-cytotoxic and non-phytotoxic nature of CNPs implies that it does not affect the growth of plants, seedling germination and healthy cell lines. It can be considered as a compatible and safe material for MCF 10a cell lines and plants.

Oral health is a critical component of overall health and well-being. Dental caries and periodontitis are two of the most common oral diseases and, when not treated, can have irreversible sequelae and overall psychosocial and physiologic impact on individuals, diminishing quality of life. The burden of advanced dental caries and periodontal disease leading to tooth loss is severe. Physicians and allied medical professionals can help in early detection of dental caries, abscess, and periodontal diseases and initiate management followed by prompt referral to dental colleagues.

The fine structure in an Fe-10Ni-1.0Mo-0.6Mn-0.6Cr-0.08V-0.1C (wt pct) steel in a multi-step heat-treated condition called ‘QLT’ is understood by tracking its evolution in each step using transmission electron microscopy (TEM) and atom probe tomography; further, the consequence of high strain-rate deformation on the site-specific change in the QLT microstructure is examined by microdiffraction and energy dispersive spectroscopy in the TEM. The QLT treatment results in two generations of austenite (arising from the L- and the T-step) with differing Ni content. The primary focus of this study is on the thermal and mechanical stability of the precipitated austenite and the influence of austenite chemistry and size on the stability. Kolsky bar compression experiments were conducted to isolate a situation where an adiabatic shear band propagated partway through the specimen. Examination of the microstructure in such a specimen showed both generations of austenite to be present far from the shear band, ahead of the shear band and adjacent to the shear band. The austenite immediately ahead of the shear band was fragmented. Within the shear band, evidence was found for deformation-induced transformation to martensite. These findings are discussed within the context of improved damage tolerance and ballistic resistance observed earlier in field tests.

Laves phases belong to the group of tetrahedrally close-packed intermetallic phases, and their crystal structure can be described by discrete layer arrangements. They often possess extended homogeneity ranges and the general notion is that deviations from stoichiometry are accommodated by anti-site atoms or vacancies. The present work shows that excess Nb atoms in a Nb-rich NbFe2 C14 Laves phase can also be incorporated in various types of planar defects. Aberration-corrected scanning transmission electron microscopy and density functional theory calculations are employed to characterize the atomic configuration of these defects and to establish stability criteria for them. The planar defects can be categorized as extended or confined ones. The extended defects lie parallel to the basal plane of the surrounding C14 Laves phase and are fully coherent. They contain the characteristic Zr4Al3-type (O) units found in the neighboring Nb6Fe7 µ phase. An analysis of the chemical bonding reveals that the local reduction of the charge transfer is a possible reason for the preference of this atomic arrangement. However, the overall layer stacking deviates from that of the perfect µ phase. The ab initio calculations establish why these exceptionally layered defects can be more stable configurations than coherent nano-precipitates of the perfect µ phase. The confined defects are observed with pyramidal and basal habit planes. The pyramidal defect is only ~1 nm thick and resembles the perfect µ phase. In contrast, the confined basal defect can be regarded as only one single O unit and it appears as if the stacking sequence is disrupted. This configuration is confirmed by ab initio calculations to be metastable.

The EXO-200 experiment searched for neutrinoless double-beta decay of $^{136}$Xe with a single-phase liquid xenon detector. It used an active mass of 110 kg of 80.6%-enriched liquid xenon in an ultra-low background time projection chamber with ionization and scintillation detection and readout. This paper describes the design and performance of the various support systems necessary for detector operation, including cryogenics, xenon handling, and controls. Novel features of the system were driven by the need to protect the thin-walled detector chamber containing the liquid xenon, to achieve high chemical purity of the Xe, and to maintain thermal uniformity across the detector., Manuscript updated in response to JINST reviewer comments

Partitioning of C during tempering of quenched Fe-9.6Ni-0.5C-0.6Mn-0.6Mo-0.7Cr-0.1V (at.%) steel is determined by atom probe tomography and the resulting microstructure is described. The precipitated austenite size, together with its C and Ni content control its thermal stability and these can vary differently with tempering time and temperature. Thus, both austenite and strong carbide formers compete for the available C early in the process. Due to widely different transport kinetics, C likely plays a dominant role early but is either fully consumed or its role diminishes by dilution, and Ni partitioning eventually takes over as the austenite stability-controlling species.

The creep behavior of a fully lamellar FeAl/FeAl2 eutectoid alloy was shown to exhibit a minimum creep rate and the absence of a pronounced steady state regime. To reveal the underlying mechanisms of creep leading to the macroscopic response described above, comprehensive TEM investigation of several crept specimens were performed. In the early stages of creep, the FeAl phase primarily carries creep deformation by dislocation motion, whereas FeAl2 remains mostly plastically undeformed, except in certain locations near colony boundaries where the lamellar structure is disrupted/absent. Within the colonies, where the lamellae are intact, deformation is accommodated at the FeAl/FeAl2 interface, resulting in an increase in interface dislocations. This continues to be the case at the minimum creep rate. With further progression in creep, FeAl2 begins to participate in the process of plastic deformation in a more substantive manner through twinning and slip, while FeAl continues to plastically deform and dynamically recover. Further beyond the minimum, the lamellar structure adjacent to the colony boundaries breaks down, and these areas become the primary contributors to creep and results in a continuous loss in creep resistance. Based on these observations in the fully lamellar material, the creep response of off-eutectoid Fe-58Al and Fe-62Al as well as single-phase FeAl2 are explained.

FAO AquaCrop is a simulation model that predicts the effects of soil, climate, water and crop growth on water productivity, yield and its attributes of various crops. In the present study, performance evaluation of AquaCrop model for maize was assessed for rabi maize during 2015 at Water Technology Centre, College of Agriculture, Rajendranagar, Hyderabad. The experiment was laid in a randomized block design with eight treatments in three replications. The treatments comprised of surface and drip irrigation schedules based on Epan viz., surface irrigation at 0.6 IW/CPE ratio (T1), 0.8 IW/CPE ratio (T2), 1.0 IW/CPE ratio (T3), 1.2 IW/CPE ratio (T4), drip irrigation at 0.6 Epan (T5), 0.8 Epan (T6), 1.0 Epan (T7) and 1.2 Epan (T8). The model was evaluated using crop data resulted from the experiment under varying water application methods and levels. Simulation performance was assessed with statistical parameters viz., statistical co-efficient of determination (R2), prediction error (Pe), model efficiency (E), root mean square error (RMSE) and mean absolute error (MAE). The model results are in quite agreement with practical values for grain yield, biomass and water productivity with model efficiency of 0.99, 0.92 and 0.71, coefficient of determination (R2) of 0.90, 0.91 and 0.93 with an RMSE of 0.24, 0.10 and 0.05, respectively. The model prediction errors in simulation of grain yield, biomass and water productivity under all treatments ranged from 1.4% to 11.9%, 1.4% to 16.1% and 4.85% to 25.9%, respectively. The highest and lowest prediction accuracy for grain yield, biomass and water productivity were in drip irrigation at 1.2 Epan and surface irrigation at 0.6 IW/CPE ratios. It is inferred that FAO AquaCrop model is suitable for predicting grain yield, biomass, water productivity and green canopy cover with acceptable range of under and over predictions for maize in semi-arid tropical climate.

Crystal plasticity finite element (CPFE) modeling of multi-phase, third generation advanced high strength steel (3GAHSS) requires finding the hardening parameters of slip systems operating in different phases (e.g. FCC, BCC, BCT). It is common to see the Schmid law used to model the deformation of BCC crystals. However, researches by Bassani and others have shown that BCC crystals could obey the non-Schmid law. In this paper we examined the differences between using a CPFE model based on the Schmid versus a non-Schmid law to model the uniaxial compression of single crystal ferrite micropillars with distinct orientations carved out of dual phase DP980 and three-phase QP980 steel sheets. To accurately model the changing hardening rate of the single crystal, a new exponential hardening model was developed that would differentially harden slip systems. Criteria for transitioning from stage I to stage II hardening of single crystals were also developed and verified. Finally, it was shown that it is not sufficient to use only one single crystal micropillar compression force-displacement curve for the calibration of the non-Schmid CPFE model. The predictions of the resulting model would be unreliable, and its accuracy highly dependent on the orientation of the micropillar chosen for calibration. However, when two mircopillar compression force-displacement curves were used for calibration, the model's predictions were consistently accurate. Using more than two curves for calibration did not result in significant improvements.

The past decade has seen a surge in the use of e-cigarettes, which has prompted the medical community to assess any associated potential health hazards. A major concern was the risk of cancer. Chemical analysis of e-cigarettes has shown the presence of volatile organic compounds with the potential for carcinogenicity. Comparative toxicology analysis has shown e-cigarette to have relatively lower dosages of toxins than conventional combustible cigarettes. Based on comparative analysis, e-cigarettes have been increasingly advocated as a safe alternative to conventional cigarettes. It is vital to recognize that presence of relatively lower toxin level does not preclude carcinogenic potential. The nicotine present in the e-cigarette was presumed to be the major cytotoxic agents, thus nicotine-free e-cigarette was considered as inert. On the contrary, experimental studies on oral cell lines have shown DNA strand breaks on exposure to e-cigarette vapors with or without nicotine. In addition, dysregulations of genes associated with carcinogenic pathways have also been demonstrated in oral tissues exposed to e-cigarette vapors. Despite alarming molecular data, the oral carcinogenic potential of e-cigarette remains unclear, which can be attributed to the lack of long-term prospective and large-scale case-control studies. As e-cigarette users often have other well-established risk factors (conventional cigarette smoking, alcohol, etc.) as associated habits, it is difficult to assess e-cigarette as an independent risk factor for oral cancer. Thus, the present manuscript aims to review the published literature using the Brad Ford Hill criteria of causation to determine the oral carcinogenic potential of e-cigarettes.

Oxygen is a very important factor in determining radiosensitivity because it enhances the damage to cellular components caused by ionizing radiation, although mechanisms involved in UV irradiation damage may overlap ionizing radiation effects. This paper emphasizes chemical protection against damage by ionizing radiation and predominantly against the effects of photons (and gamma radiation). It is possible that free radicals and their products induced by ionizing radiation can interact with reactive oxygen species formed during normal processes, such as superoxide and hydrogen peroxide produced by phagocytic cells or during enzymatic processes (xanthine oxidase activity; enzymes involved in eicosanoid metabolism). Metals such as iron can promote free radical damage, whereas some bound metals have radioprotectant potential, e.g., metallothionein and ceruloplasmin. There is increasing evidence that maintenance of the proper oxidation-reduction state of cells by the interconversion of the peptide sulfhydryl glutathione (GSH), and its disulfide form (GSSG) is a factor in the modulation of cellular radiosensitivity. Other protein and nonprotein sulfhydryls may also play a role both as targets of radiation damage and as protectors. Other physiological antioxidants (vitamin E) and antioxidant enzymes are interrelated in their function of controlling oxidative processes. This review concentrates on the role of oxygen, glutathione, andmore » antioxidant enzymes in radiosensitivity and how exogenous chemicals interact with these endogenous factors.« less

Summary 2D-Electrical Resistivity Tomography of Mesoarchaean Chromitite Bands from Kathpal in Sukinda Ultramafic Complex, Odisha.

Summary Application of Geophysical Methods (Gravity and Magnetics) to Chromite Prospecting: An example from Kathpal Area, Sukinda, Orissa.

Stress-controlled uniaxial cyclic tensile tests were conducted on binary Mo-27 at% Re and Mo-0.3 at% Si solid solutions as a function of temperature and compared against the previously reported cyclic response of pure Mo. The Mo-27 at% Re alloy with a recrystallized grain size of ~30 µm was evaluated in the temperature range 25 °C–800 °C at R=0.1 and stress range that was 80% of the ultimate tensile strength (UTS); a peak in fatigue life was observed between 300 °C and 500 °C. The decrease in fatigue life at the higher temperatures of 700 °C and 800 °C is attributed to dynamic strain aging. Transmission electron microscopy of the cyclically-deformed alloy revealed parallel bands of dislocation at room temperature that transitioned to a uniform cell structure at 500 °C and back to orthogonal planar arrays at 800 °C. The as-extruded Mo-0.3 at% Si alloy was evaluated from 25 °C to 1200 °C and showed superior fatigue life and ratcheting strain resistance as compared to pure Mo and the Mo-27 at% Re alloy (within the temperature range where data were available for comparison). The superior resistance is attributed to the high density of dislocations within the material in this mostly unrecrystallized state rather than Si in solid solution. Above 800 °C, the ratcheting strain increases and fatigue life decreases rapidly with increasing temperature and is associated with dynamic recovery.

Background Spin in randomized controlled trial (RCT) abstracts can misguide clinicians. In this cross-sectional analysis, the authors assessed the prevalence of spin in RCT abstracts and explored the factors potentially influencing it. Methods In this cross-sectional analysis, the authors conducted a systematic search in top 10 dental journals based on Eigenfactor score and selected RCTs published in 2015 with statistically nonsignificant primary outcomes. The dentistry disciplines covered in these journals include general dentistry, dental research, oral implantology, endodontics, oral surgery, periodontology, and oral oncology. In these RCT abstracts, the authors assessed the prevalence of 3 different categories of spin and factors that could influence its presence using the t test and χ2 test. Results Spin assessment performed in the included 75 RCTs revealed the existence of spin in 23 abstracts (30.7%). Associations between the presence of spin in abstracts and the variables international collaborations, commercial support type, number of treatment arms, and journal impact factor were found to be statistically nonsignificant (P ≥ .05). Conclusions Approximately one-third of the 75 RCT abstracts published in high-impact dental journals in 2015 with nonsignificant outcomes presented with some form of spin, irrespective of funding type and journal impact factor. Practical Implications Clinicians should be aware of the potential existence of spin in abstracts and be diligent in reading and appraising the full trial before incorporating its recommendations in clinical practice.

The Brahmo (or Brahma) Samaj (‘Society of Brahma’) is the name of a theistic society founded by Raja Rammohun Roy in Calcutta in 1828. It advocated reform, and eventually abolition, of the traditional caste system, as well as legislation aimed at improving the social status of women and greater protection of children. Also dedicated to Hindu religious reform, the Brahmo Samaj stressed a monotheistic doctrine with a policy of tolerance and respect for all major religions of the world. The society split into two factions in 1866, largely over the issue of the speed of reform. Another split occurred in 1878 over whether the society’s constitution was to be fully democratic. The democratic wing, called the Sadhāraṇ Brahmo Samaj (‘Universal Brahma Society’), is still active in India.

Machine learning (ML) is the ability of computers to learn from data autonomously. It is a core branch of artificial intelligence (AI), which is defined as the ability of a machine to replicate the intellectual processes of humans independently.1,2 The evolution of the microprocessor for home computers resulted in increased computing speed, efficient data collection, storage, and retrieval capacity. Thus AI techniques have evolved, which led to the discovery of artificial neural networks which are computer modeling algorithms mimicking the human brain.3-6 AI has developed to an extent that it can exceed the human brain in board games such as chess, television games, image recognition, and spam e-mail filtering. In addition to engineering, arts, and finance, extensive progress has been made to integrate ML in the field of medicine, especially oncology.

Mg single crystals were compressed along [0 0 0 1] at room temperature to various stress levels (40, 80, 120, 160 and 320 MPa) and the evolution of dislocation structure with stress increment was investigated by TEM. 〈c+a〉 slip is confirmed to be the dominant deformation mode; the predominance of edge dislocation debris lying along the implies that screw 〈c+a〉 dislocations are more mobile than their edge counterpart. The 〈c+a〉 edge dislocation may dissociate into 〈c〉 and 〈a〉 dislocations, and the latter can extend further on the basal plane and bound a basal-stacking fault. Numerous 〈c+a〉-type dislocation loops are generated during deformation and together with point defects and edge dipoles, contribute to the observed high work hardening rate. The smaller (

The commonly encountered osteochondroma is a benign tumour that usually arises from the metaphyseal region of long bones, demonstrates mature bone with a cartilaginous cap, a continuation of the medullary cavity with that of the long bone and grows away from the joint till achievement of skeletal maturity. Extraskeletal para-articular osteochondroma, also known as intracapsular chondroma, arises from the capsule and/or connective tissue adjacent to the capsule due to osteocartilaginous metaplasia and occurs most frequently around the knee, particularly the infrapatellar fat pad of Hoffa.1 Extraskeletal para-articular osteochondroma is a rare entity with only 23 cases reported till 19972 and about 40 cases by 2006.3 This article reports another giant intra-articular extrasynovial osteochondroma of the knee which was surgically excised and discusses the clinical and imaging features, the histology and purported pathogenesis, and the differential diagnosis.

In a previous paper, the microstructure, monotonic, and cyclic response of as-drawn similar to 100 pm diameter MP35N low-Ti alloy wire were presented and discussed. In this sequel paper, the effects of annealing the same cold-drawn wire on microstructure and mechanical properties are examined. Specifically, segments of the wire were annealed for 1 h at 973 K, 1023 K, 1073 K, 1123 K and 1173 K in a vacuum furnace. The resulting microstructure was characterized by SEM, EBSD and TEM and compared to the asdrawn microstructure. In-situ heating in the TEM of MP35N ribbon in a similarly cold worked condition enabled corroboration of microstructure evolution during annealing. Annealed wires were tested monotonically and cyclically in uniaxial tension at room temperature, the latter using a stress ratio (R) of 0.3. In addition, the annealed wires were tested cyclically at R= -1 using the rotating beam bending fatigue test. Post-deformation structures and fracture surfaces were characterized using TEM and SEM respectively. Annealing the cold drawn wire results in recrystallization and grain growth; the extent is dependent on the annealing temperature. Deformation twin boundaries in the as-drawn structure illustrate faceted bulging and eventually complete elimination, the microstructure evolving into fine equiaxed grains containing coarser annealing twins with no significant change in texture. Yield strength decreases rapidly with recrystallization to almost half the value of the as-drawn condition, but is accompanied by an increase in modulus (by similar to 25%) and tensile elongation reaching 30%. Cyclic response by the way of S-N curves is not enhanced by annealing on an absolute stress scale (due to the loss in yield strength) although the annealed wires are cyclically superior when the stress data are normalized by yield stress. (C) 2015 Elsevier B.V. All rights reserved.

On the Al-rich side of the Fe-Al binary system, the eutectoid decomposition of Fe5Al8 into B2-ordered FeAl and triclinic FeAl2 in the composition range of 55–65 at.% Al produces an ultrafine lamellar microstructure. The compression creep behavior of such two-phase intermetallic materials was investigated in the temperature range 600–800 °C under constant stress. In addition to the fully lamellar Fe-61Al alloy, Fe-58Al and Fe-62Al that included, pro-eutectoid FeAl and FeAl2, respectively, were characterized in terms of their microstructure and creep response. For all microstructures, the strain rate as a function of time and strain exhibits a distinct minimum instead of a steady state creep regime. Microstructure instability, primarily in the vicinity of colony boundaries, is identified as the main reason for the increase in strain rate beyond the minimum. In contrast, lamellar coarsening is shown to be only a secondary factor influencing creep response for the conditions investigated. In comparison to single phase FeAl, the fully lamellar FeAl-FeAl2 shows enhanced creep resistance while the presence of either pro-eutectoid phase leads to a relative deterioration of the creep resistance.

The deformation response of low Ti ( R =−1) and in tension–tension fatigue ( R =0.3), appeared to be initiation-controlled and sensitive to the presence of extraneous second phase inclusions identified as Al 2 O 3 particles. Cyclically-deformed as - drawn wire samples displayed extensive de-twinning and multiple twin variants formation.

Three phase α-Mo–Mo 3 Si–Mo 5 SiB 2 alloys of various compositions, namely Mo–6Si–5B, Mo–9Si–8B, Mo–10Si–10B and Mo–13Si–12B (at.%) were processed by a powder metallurgical (PM) route. Increasing the Si and B concentration in these Mo–Si–B alloys resulted in increasing volume fractions of the intermetallic phases Mo 3 Si (A15) and Mo 5 SiB 2 (T2) and the distribution of the three phases present in these alloys was dependent on the volume fractions of the individual phases. Above volume fractions of about fifty percent, bcc Mo solid solution (α-Mo) formed the matrix. Consequently, Mo–6Si–5B and Mo–9Si–8B alloys, which possessed a continuous α-Mo matrix provided increased fracture toughness at ambient temperatures. Additionally, a decreased BDTT of about 950 °C is caused by the homogeneous α-Mo matrix. In contrast, Mo–13Si–12B with 65 vol.% of the intermetallic phases that formed the matrix phase in this material had a BDTT value higher than 1100 °C, while the strength at elevated temperatures up to 1300 °C was significantly increased compared to alloys that have the α-Mo matrix. Alloy compositions with ≥50 vol.% of intermetallic phases (corresponding to alloys containing a minimum of 9 at.% Si and 8 at.% B) were oxidation resistant with minimal mass loss under cyclic conditions for 150 h at 1100 °C due to the formation of a dense borosilicate glass layer that protects the material surface.

Deformation response of ferrite and martensite in a commercially produced dual-phase sheet steel with a nominal composition of 0.15% C–1.45% Mn–0.30% Si (wt.%) was characterized by nanoindentation and uniaxial compression of focused ion beam-milled cylindrical micropillars (1–2 μm diameter). These experiments were conducted on as-received and pre-strained specimens. The average nanoindentation hardness of ferrite was found to increase from ∼2 GPa in the as-received condition to ∼3.5 GPa in the specimen that had been pre-strained to 7% plastic tensile strain. Hardness of ferrite in the as-received condition was inhomogeneous: ferrite adjacent to ferrite/martensite interface was ∼20% harder than that in the interior, a feature also captured by micropillar compression experiments. Hardness variation in ferrite was reversed in samples pre-strained to 7% strain. Martensite in the as-received condition and after 5% pre-strain exhibited large scatter in nanoindentation hardness; however, micropillar compression results on the as-received and previously deformed steel specimens demonstrated that the martensite phase in this steel was amenable to plastic deformation and rapid work hardening in the early stages of deformation. The observed microscopic deformation characteristics of the constituent phases are used to explain the macroscopic tensile deformation response of the dual-phase steel.

Recrystallized, commercially pure Mo, binary Mo–27 at.% Re, and as-extruded and variously annealed Mo–0.3 at.% Si alloys were tested in uniaxial tension as a function of temperature in vacuum. The Mo–Re solid solution is significantly stronger than Mo and retains the strength to at least 800 °C. The alloy exhibits serrated flow in the 500 °C–800 °C range and this is accompanied by a continuous decrease in ductility with increasing temperature in this temperature range. The recrystallized Mo–0.3 at.% Si alloy is softer than pure Mo at room temperature and has high ductility (~ 60% tensile elongation). In the worked condition, it is significantly stronger (σ y > 600 MPa) but still is ductile at room temperature (~ 10% tensile elongation). The observation of ductility at room temperature in this Mo–0.3 at.% Si solid solution alloy has important implications for multiphase ternary Mo–Si–B alloys of technological interest.

Incipient plasticity in Mg single crystals was investigated using the pop-ins generated during spherical nanoindentation on (0 0 0 1), (1 0 −1 2) and (1 0 −1 0) surfaces. Representative deformed regions extracted from underneath indents by means of focused ion beam machining were examined by transmission electron microscopy (TEM) to identify the deformation mechanisms. Anisotropic elastic Hertzian contact theory was used to calculate indentation Schmid factors and the relevant resolved shear stresses at pop-in from the load–displacement curves. The pop-in statistics in conjunction with the TEM analysis showed that the most likely deformation mechanism responsible for pop-in is slip via 〈a〉 dislocations even in the case of indentation along the c-axis.

In this article, our current understanding on the effects of Zr additions on the properties of three-phase Mo-Si-B alloys is reported. This novel group of materials having high melting points around 2000°C have been identified as potential alloy systems for structural applications at temperatures beyond 1200°C, e.g., for substituting or supplementing state-of-the-art nickel-base superalloys in the power generation industry. In earlier work, we developed various Mo-Si-B materials with very good high-temperature deformation behavior and, in addition, that satisfy oxidation performance. Minimum brittle-to-ductile transition temperatures of around 950°C, however, do not meet the requirements for high-grade stressed structural materials. Therefore, in a second trial, we investigate the influence of the alloying element Zr (which was already proven to increase the strength as well as the ductility of a single-phase Mo-Si alloy) on three-phase Mo-Si-B alloys.

Compression of single-crystal magnesium along the [0 0 0 1] direction at room temperature confirmed a high yield stress, high work-hardening and minimal plastic deformation prior to fracture. Post-deformation examination revealed the dominance of c + a slip; straight and zig-zag dislocations and numerous fine dislocation loops, all with the 〈11–23〉 Burgers vector, were observed. These are thought to be responsible for the high work-hardening behavior. Extension and contraction twins were present, but only occasionally. Extension twins were shown to occur during unloading.

Magnesium bicrystals were grown with symmetric and asymmetric tilt boundaries about the [10–10] axis using the vertical Bridgman technique. Isothermal constant load tensile tests were conducted on these bicrystals in the temperature range 300–500°C and relative displacements of the two grains were measured to obtain an appreciation for grain boundary motion characteristics. Coupled grain boundary motion was noted in almost all cases with the degree of tangential motion versus migration changing with tilt misorientation, temperature and applied stress. Specifically, within the family of symmetric bicrystals evaluated, a minimum in grain boundary displacement in the specimen plane was observed at a tilt misorientation of 20°. In specific stress/temperature regimes, rigid body sliding was observed for the particular case of a 35° asymmetric tilt misorientation. The ease of basal and prism slip in magnesium at the temperatures considered and the consequential impingement of intragranular dislocations on the b...

Monotonic tensile tests and uniaxial load-controlled tension–tension cyclic tests were performed on commercial purity (99.99%) molybdenum in the recrystallized state in the temperature interval spanning RT (25 °C) to 500 °C range. Cyclic deformation behavior was characterized by analyzing the ratcheting strain, cyclic hardening response, and fatigue life. The response of unrecrystallized and recrystallized Mo was compared at room temperature; the influence of test variables including mean stress, stress amplitude and R ratio on ratcheting strain in recrystallized Mo at room temperature was also examined. The magnitude and rate of ratcheting strain evolution with cycles appear to depend on both the mean stress and the stress amplitude. Microstructural evolution during cyclic loading was characterized by conducting interrupted tests at room temperature as well as at 400 °C. Observations confirm dislocations cell structure formation during cyclic plastic deformation at room temperature and at 400 °C, the process occurring more rapidly at the higher temperature; in addition, at the higher temperature some of the cell walls appeared to have transformed into subgrain boundaries, suggesting partial recovery.

Oral Diseases (2012) 18, 625–632 Non-exposed bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a newly reported complication arising from bisphosphonate therapy that presents with atypical symptoms and no apparent mucosal fenestration or exposure of necrotic bone. The clinical observation of the presence of necrotic bone underneath normal epithelial coverage was not conclusive for the diagnosis of BRONJ based on current guidelines established by the American Association of Oral and Maxillofacial Surgeons (AAOMS) and the American Society for Bone and Mineral Research (ASBMR), which specify the presence of clinically exposed necrotic bone for more than 8 weeks. Hence, the purpose of this review is to critically assess the current guidelines for diagnosis and management of BRONJ and propose a modified staging system and treatment guidelines to properly address the non-exposed variant of BRONJ lesions.

The asymmetric unit of the title salt, C4H12N22+·2C6H6NO3S−, consists of half a piperazindiium dication, located about an inversion centre, and a 4-aminobenzenesulfonate anion. The piperazine ring adopts a chair conformation. In the crystal, the cations and anions are linkedviaN—H...O and C—H...O hydrogen bonds, forming a three-dimensional framework. Within the framework there are C—H...π interactions and the N—H...O hydrogen bonds result in the formation ofR44(22) andR34(13) ring motifs.

In polycrystalline materials that fail by transgranular cleavage, it is known that crystallographic misorientation of preferred fracture planes across grain boundaries can provide crack growth resistance; despite this, the micromechanisms associated with crack transmission across grain boundaries and their role in determining the overall fracture resistance are not well understood. Recent studies on diverse structural materials such as steels, aluminum alloys and intermetallics have shown a correlation between fracture resistance and the twist component of grain misorientation. However, the lack of control over the degree and type of misorientation in experimental studies, combined with a dearth of analytical and computational investigations that fully account for the three-dimensional nature of the problem, have precluded a systematic analysis of this phenomenon. In this study, this phenomenon was investigated through in situ crack propagation experiments across grain boundaries of controlled twist misor...

Greenhouse technology provides favorable microclimate for year round cultivation of crops. Floricultural production in the greenhouse is an attractive venture for subtropical India due to its economic and aesthetic value. However, production and quality of flowers suffer due to high summer temperatures. Hence, development of a reliable model to predict the microclimate of greenhouse is necessary to manage the crop production and to optimize the design. Experiments were conducted in two different shape and size of greenhouses to evaluate the microclimate and crop performance. A simple dynamic model was developed to predict air temperature, vapor pressure and canopy temperatures. Submodels of natural ventilation and crop transpiration constituted the sensible and latent heat transfers in the greenhouse. The model was validated for Gerbera crop cultivation during winter and summer seasons. Good agreement was found between the predicted and observed values of temperature with RMSE values of 0.73 °C and 0.87 °C during winter and summer seasons, respectively. Sensitivity analysis of the model showed that width of side opening and angle of roof vent influenced the model performance considerably. It was concluded that the model can be used as a design tool for prediction of microclimate in the greenhouse for floricultural production.