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A novel hard composite solid lubricant coating combining TiN and MoSxhas been developed using pulsed DC closed-field unbalanced magnetron sputtering (CFUBMS). The tribological and mechanical properties together with their interdependencies with the coating microstructures have been assessed and reported elsewhere. This article evaluates the machining performance and correlates the underlying tribological aspects of different TiN-MoSxcoating architectures (deposited at titanium (Ti) cathode currents of 1, 3.5, and 5 A) when dry turning AISI 1080 high-carbon steel. A comparative performance study clearly established the supremacy of the composite coating (deposited at 3.5 A Ti cathode current with ∼12 wt% of MoSx) with a hard TiN underlayer over monolayer TiN, MoSx, and other related coating architectures in terms of cutting force, tool wear, and workpiece surface roughness. The superlubricity behavior of the said composite coated tool resulted in a reduction of cutting force (by up to ∼45% compared to the uncoated tool) and exhibited a tool life of 8 min, which was eight times and more than two times longer than that of the uncoated and conventional hard TiN coated counterparts, respectively. The workpiece surface roughness, Ra, also decreased by 13 to 21% when machined with the TiN-MoSxcoated tool in comparison to the uncoated cemented carbide. [ABSTRACT FROM AUTHOR]

Agronomic management through better use of inputs benefits farmers both by enhancing productivity and profitability. A field experiment was conducted in consecutive summer seasons (2011–2013) consisting of two mulching (no mulch, polythene mulch), three hydrogel (0, 2.5, 5.0 kg ha−1), and three nutrient management treatments (organic, inorganic, and integrated) in a split–split plot design. Use of mulching and 2.5 kg hydrogel ha−1and integrated nutrient management enhanced pod, haulm, kernel and oil yields, and net economic returns. Partial factor productivity and water-use efficiency were higher under polythene mulch and 5.0 kg hydrogel ha−1. Higher nutrient uptakes were obtained under both mulching and integrated nutrient management. Use of 2.5 kg hydrogel ha−1resulted in more removal of N; P and K uptakes were higher in 5.0 kg hydrogel ha−1. Combination of three managements had a consequence of actual soil N loss, but gains in soil P and K after three cropping cycles. [ABSTRACT FROM PUBLISHER]

The paper reports an investigation into the functional response of textured surfaces with different designs that incorporated arrays of micro-dimples and grooves (40 μm diameter/width and 15 μm depth for both patterns) produced on tungsten carbide (WC) blocks by employing nanosecond (ns) and femtosecond (fs) lasers. In particular, the tribological performance of the textured WC blocks against stainless steel (SS316L) counterbody was evaluated in terms of friction and wear under dry condition compared to an untextured specimen. Friction tests were carried out on a reciprocating sliding tester while unidirectional ball-on-disc method was utilised to assess wear on the mating surfaces. The untextured surface exhibited a continuous rise in the friction coefficient from 0.15 to 0.5 from the start of the cycle to the end while the specimens textured with ns and fs lasers reached steady-state condition after 100 and 200 cycles with values between 0.35-0.45 and 0.3-0.4, respectively. Energy dispersive spectroscopy following wear tests showed a pronounced material transfer from the balls to the textured surfaces with stainless steel filling up some of the dimple and groove cavities; however, the reverse phenomenon was not apparent. Additionally, texturing with the fs laser exhibited formation of nano-ripples/structures in the produced dimples and grooves that can be further studied for creating nano-textured cutting tools or surfaces with super-hydrophobic/anti-ice properties. [ABSTRACT FROM AUTHOR]

The present study was conducted to assess the effect of soil salinity on yield attributes as well as nutrient accumulation in different plant parts of sevenBrassicacultivars from two different species raised in pot culture experiment with two levels of salinity treatments along with control corresponding to soil electrical conductivity (EC) values of 1.65 (S0), 4.50 (S1) and 6.76 (S2) dS m−1. The experiment was consisted of twelve replications in a completely randomized design. Imposition of salinity stress affected various yield attributing characters including plant height, which ultimately led to severe yield reduction. However, tolerant cultivars, CS 52 and CS 54 performed better under salt treatment showing lesser yield loss. Salinity stress reduced the nitrogen (N) content in leaves of theBrassicaplants, which reflected in decreased seed protein content. Reduced accumulation of iron (Fe), manganese (Mn) and zinc (Zn) was observed in leaf, stem and root at flowering and post-flowering stages, while CS 52 and CS 54 showed less reduction than susceptible cultivars under salinity stress. [ABSTRACT FROM AUTHOR]

According to some patented literatures, grit pull-out in single layer galvanic wheels can be arrested by a physical vapor deposited (PVD) coating on the wheels. It has been assumed, therein, the uniform high energy bombardment of TiN caused a reinforcement of the bond as well as increased the stability of the cBN layer on the core. However, an in-depth study on the performance of PVD coated grinding wheel is still lacking. The present research deals with exploring the effect of grinding parameters and substrate bias voltage on the performance of TiN coated galvanic cBN wheels compared to their uncoated counterpart in dry surface grinding of AISI 52100 hardened bearing steel. TiN was deposited at the bias voltages of 0, -60, and -90 V in an in-house PVD coating system. The coating microstructure and post-grinding condition of the wheels were observed using scanning electron microscopy (SEM) and phase detection was carried out using grazing incidence X-ray diffraction (GIXRD). With the increase in negative bias voltage, highly dense and compact structure of TiN was observed along with a reduction in column size. GIXRD indicated the formation of nickel-titanium intermetallics at the interface of TiN and nickel bond. Amongst the grinding parameters, downfeed was found to be the most influential factor on the grinding forces and specific grinding energy. Both downfeed and wheel velocity exhibited significant percentage contributions to the maximum grit depth of cut. The uncoated wheel was found to undergo many grit fractures and some pull-out during grinding. TiN deposited at 0 V bias could not prevent the fracture. However, when TiN was deposited at the bias voltages of -60 V and -90 V, such failures were noticeably restricted due to the high energy ion-bombardment and diffusion of Ti and TiN within the nickel bond and the cBN grits. [ABSTRACT FROM AUTHOR]

Abstract: Application of MoS2-based solid lubricant has extreme potential as a coating material of cutting tools because of its superlubricity against most of the engineering materials. However, a detailed study on the effect of such lubricious coating in grinding has never been carried out before. In the present research, the tribological behaviour of MoS2-Ti composite coating with TiN underlayer on electroplated nickel and braze alloy was investigated separately in comparison to TiN coated and uncoated counterparts. Grinding of AISI 52100 steel was also carried out with uncoated, TiN coated and MoS2-Ti coated (with TiN underlayer) monolayer (both electroplated and brazed) cBN wheels. The structure of the coatings and the condition of the grinding wheels were observed under SEM. In tribology test, MoS2-Ti composite coating was found to be best performing on both nickel and braze alloy in terms of coefficient of friction and depth of the wear track. Minimum variation in normal force and remarkably steady behaviour of tangential force were obtained with both MoS2-Ti coated electroplated and brazed wheels over the total experimental run. Large number of grit fracture at and above bond level with some amount of grit pull-out was observed in uncoated electroplated wheels. Uncoated brazed wheels have undergone grit breakage at bond level. However, such failures of grit were significantly arrested with both TiN and MoS2-Ti composite coatings. [Copyright &y& Elsevier]

Titanium nitride-aluminium oxide (TiN-Al2O3) is a new generation ceramic composite material having potential for many industrial applications as it possesses high resistance to thermal degradation, anti-wear and anti-abrasion properties. But conventional machining of such ceramic composite is difficult to perform for some of its peculiar properties like anisotropy, low thermal conductivity, and abrasive nature of the reinforcing phases. In the present investigation, non-conventional machining like electro discharge machining (EDM) has been carried out to machine the material. Energy dispersive X-ray spectroscopy and X-ray diffraction analysis have also been carried out on the composite matrix to verify the presence of two distinguishable phases of TiN and Al2O3. The present article reports the effects of EDM process parameters on material removal rate, electrode wear rate, radial overcut, and taper angle while machining TiN-Al2O3 composite. The characteristic features of the EDM process are explored through Taguchi L9 orthogonal array design-based experimental studies with various process parametric combinations. Finally, optimum parameter settings for each response factor are obtained and tested through verification experiments. The whole experimental study indicates that EDM has a very good potential in machining of TiN-Al2O3 ceramic composite in some particular ranges of process parameters. [ABSTRACT FROM AUTHOR]

Nanoscale elements are fabricated using bottom-up processes, and as such are prone to high levels of defects. Therefore, fault-tolerance is crucial for the realization of practical nanoscale devices. In this paper, we investigate a fault-tolerance scheme that utilizes redundancies in the rows and columns of a nanoscale crossbar molecular switch memory array. In particular, we explore the performance tradeoffs of time delay, power, and reliability for different amounts of redundancies. The results indicate an increase in fault-tolerance with small increases in delay and area utility. [ABSTRACT FROM PUBLISHER]

Nanoelectronic systems are anticipated to be highly susceptible to computation and communication noise. Interestingly, von Neumann addressed the issue of computation in the presence of noisy gates in 1952 and developed a technique called multiplexing. He proposed multiplexing architectures based on two universal logic functions, nand and maj. Generalized combinatorial models to analyze such multiplexing architectures were proposed by von Neumann and extended later by others. In this work, we describe an automated method for computing the effects of noise in both the computational and interconnect hardware of multiplexing-based nanosystems-a method employing a probabilistic model checking tool and extending previous modeling efforts, which only considered gate noise. This method is compared with a recently proposed automation methodology based on probabilistic transfer matrices and used to compute and compare the reliability of individual nand and maj multiplexing systems, both in the presence of gate and interconnect noise. Such a comparative study of nand and maj multiplexing is needed to provide quantitative guidelines for choosing one of the multiplexing schemes. The maximum device failure probabilities that can be accommodated by multiplexing-based fault-tolerant nanosystems are also computed by this method and compared with theoretical results from the literature. This paper provides a framework that can capture probabilistically quantified fault models and provide quick reliability evaluation of multiplexing architectures [ABSTRACT FROM PUBLISHER]

As manufacturing technology reaches nanoscale, architectural designs need to accommodate the uncertainty inherent at such scales. These uncertainties are germane in the minuscule dimension of the devices, quantum physical effects, reduced noise margins, system energy levels reaching computing thermal limits, manufacturing defects, aging, and many other factors. Defect-tolerant architectures and their reliability measures will gain importance for logic and micro-architecture designs based on nanoscale substrates. Recently, the Markov random field has been proposed as a model of computation for nanoscale logic gates. This opens up new possibilities in designing logic and architecture where the conventional Boolean logic is replaced by a notion of an energy distribution function based on Gibbs distribution. In this computational scheme, probabilities of energy levels at various gate inputs and interconnects are considered, and belief propagation is used to propagate these probability distributions from the primary inputs to the primary outputs of a Boolean network. In this paper, we take this approach further by automating this computational scheme and belief propagation algorithm. We have developed MATLAB-based libraries for fundamental logic gates that can compute probability distributions and entropies at the outputs for specified discrete input distributions and in the presence of noise at the inputs and interconnects. Our tool automates the evaluation of reliability measures of combinational logic blocks. The effectiveness of this automation is illustrated in this paper by automatically deriving various reliability results for defect-tolerant architectures, such as triple modular redundancy (TMR), cascaded TMR, and multistage iterations of these. Also, signal noise is modeled as uniform and Gaussian distributions at the inputs and interconnects, so as to evaluate reliability-redundancy tradeoffs of these architectural configurations taking into account such noise models. [ABSTRACT FROM PUBLISHER]

A simplified analysis has been attempted on flame stabilization by bluff-body based on a physical model. The proposed theoretical model predicts with fair accuracy the experimental results of Zukoski and Marble (1956), Fetting el at. (1959) and also of the present investigation. Implications of theoretical and experimental results have been discussed. [ABSTRACT FROM PUBLISHER]

• Straw characterization was intended for bioethanol, biochar, compost and mushroom production. • Straw of 18 prominent rice cultivars was characterized though biochemical, SEM, FTIR. • Straw was grouped for production of biochar, bioethanol, compost, mushroom production. • Study showed the potential of straw for large and small-scale industrial applications. Rice straw is a useful bio-resource with worldwide annual production of approximately 731 million tons. However, this valuable biomass is unfortunately burnt on field as waste that causes air pollution, global warming, plant nutrient losses and environment menace. About 60% of rice straw produced in Asia in general and India in particular is burnt in field. As for the basic requirement to predict their suitability for best alternative industrial uses biochemical, morphological and chemical (functional group) characterization of straws of 18 most widely grown rice cultivars from eastern region of India was carried out. Biochemical characterization was done on the basis of cellulose, hemicellulose, lignin and silica content. The surface morphology of straws was observed through Scanning Electron Microscopy (SEM), while, presence of functional groups were analyzed through Fourier Transform Infrared (FTIR) spectroscopy. Primarily, quantified biochemical profiles were used to group cultivars for best alternate uses of straw like bio-ethanol, biochar, compost and mushroom production. Morphological feature (from SEM) of straw and functional group (through FTIR) were used to support the grouping. Cultivars with higher hemicelluloses and cellulose with low to medium lignin and Si were better suited for bio-ethanol production while, straw having higher lignin and low to medium cellulose and hemicellulose were selected for biochar. Therefore, considering all the three characterization methods (chemical composition, morphological features, presence or absence of functional groups), we found straws of rice cultivars, Tapaswini and IR 64 were best suited for bio-ethanol and biochar production, respectively. There are overlapping as well as contradictory observations found during grouping, when the three approaches were followed together. This indicate that the grouping of straw for better alternative uses could be done by biochemical and morphological characterization but this should be validated in small scale at farm or factory level for final recommendation. [ABSTRACT FROM AUTHOR]

Stability of soil organic carbon (SOC) is pre-requisite for stabilization of C leading to long-term C sequestration. However, development of a comprehensive metric of SOC stability is a major challenge. The objectives for the study were to develop novel SOC stability indices by encompassing physical, chemical, and biochemical SOC stability parameters and identifying the most important indicators from a Mollisol, an Inceptisol, a Vertisol, and an Alfisol under long-term manuring and fertilization. The treatments were control, 100%NPK, 50% NPK+ 50% N through either farmyard manure, cereal residue, or green manure. SOC stability indicators were selected, transformed and integrated into unique SOC stability indices via conceptual framework and principal component analysis. Principal component analysis identified Al-macroaggregate, humic acid C-microaggregate, microaggregate-C, particulate organic matter-C-macroaggregate and polyphenol-microaggregate as the important SOC stability indicators. The principal component analysis -based SOC stability index varied from 0.2 to 0.9, 0.1 to 0.5, 0.2 to 0.6, 0.1 to 0.5 for Mollisol, Inceptisol, Vertisol and Alfisol, respectively. The SOC-stability index derived from conceptual framework and principal component analysis significantly lined up well with one another, although NaOCl-Res-C showed a high correlation with both conceptual framework (r = 0.8) and principal component analysis-based (r = 0.7) SOC stability indexes, suggesting that both methods might be used to quickly assess SOC stability in four soil orders. Overall, 50%NPK+50%N by farmyard manure or green manure emerged as the most effective management practices for enhancing stability of SOC in Mollisol, Inceptisol, Vertisol, and Alfisol of India which might act as major C sink in rice-wheat and maize-wheat cropping systems. The other aspect of C sequestration is to enhance agricultural productivity without depending much on expensive chemical fertilizers. The model yardstick thus developed for assessing SOC stability might be useful to other systems as well., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The aus (Oryza sativa L.) varietal group comprises of aus, boro, ashina and rayada seasonal and/or field ecotypes, and exhibits unique stress tolerance traits, making it valuable for rice breeding. Despite its importance, the agro-morphological diversity and genetic control of yield traits in aus rice remain poorly understood. To address this knowledge gap, we investigated the genetic structure of 181 aus accessions using 399,115 SNP markers and evaluated them for 11 morpho-agronomic traits. Through genome-wide association studies (GWAS), we aimed to identify key loci controlling yield and plant architectural traits.Our population genetic analysis unveiled six subpopulations with strong geographical patterns. Subpopulation-specific differences were observed in most phenotypic traits. Principal component analysis (PCA) of agronomic traits showed that principal component 1 (PC1) was primarily associated with panicle traits, plant height, and heading date, while PC2 and PC3 were linked to primary grain yield traits. GWAS using PC1 identified OsSAC1 on Chromosome 7 as a significant gene influencing multiple agronomic traits. PC2-based GWAS highlighted the importance of OsGLT1 and OsPUP4/ Big Grain 3 in determining grain yield. Haplotype analysis of these genes in the 3,000 Rice Genome Panel revealed distinct genetic variations in aus rice.In summary, this study offers valuable insights into the genetic structure and phenotypic diversity of aus rice accessions. We have identified significant loci associated with essential agronomic traits, with GLT1, PUP4, and SAC1 genes emerging as key players in yield determination., (© 2024. The Author(s).)

The full behaviour of natural clay minerals in soil organic carbon (SOC) stabilization in the presence of oxides and external C inputs is yet unknown. Thus, an incubation experiment was conducted in a sand-clay mixture with different soil clay fractions (SCFs) obtained from Alfisol, Inceptisol, Mollisol, and Vertisol in the presence of wheat residues to compare their C stabilization capacity. The C mineralization rates were higher in 1:1 type dominated SCFs (Alfisol and Inceptisol) compared to 2:1 interstratified mineral dominated SCFs (Vertisol). Wheat residues as C source altered SCFs' abilities to stabilize SOC at only moderate dosages of application (3-12 g kg -1 ). C mineralization and microbial biomass carbon (MBC) fell by 40% and 30%, respectively, as the amount of clay increased from 7.5 to 40%. However, removing sesquioxides from the SCFs boosted C mineralization and MBC by 22% and 16-32%, respectively, which matched with higher enzymatic activities in the sand-clay mixture. The increased C stabilization capacity of Vertisol-SCF may be attributed to its greater specific surface area (SSA) (506 m 2  g -1 ) and cation exchange capacity (CEC) [meq/100 g]. Regression analysis revealed that SSA, CEC, and enzymatic activity explained approximately 86% of total variations in C mineralization. This study highlighted the critical role of 2:1 expanding clay minerals and sesquioxides in greater stabilization of external C input compared to its 1:1 counterpart. It also implied that the role of mineralogy or texture and sesquioxides levels in different soils (Vertisol, Mollisol, Inceptisol, Alfisol) should be prioritized while adding crop residues to reduce C footprint and enhance sequestration., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)