Minor Increment Research Articles

The Effect of the Surface Treatment on TiO2 Particles When Used as a Filler on Crystallization and Mechanical Properties of Polylactic Acid Composites. Case of Study: Silane Coupling Agents and Dicarboxylic Acids Were Used as Surface Modifiers

ABSTRACT This article analyzes the effect of the type of surface modification (using silane coupling agents and dicarboxylic acids) on titanium dioxide particles used as fillers in polylactic acid composites, which were exposed to a photodegradative process. The thermomechanical properties of the composites were analyzed; it was found that the silane coupling agent with Imidazole allowed the composites to have Young’s modulus values 60% lower than the composite without filler. On the other hand, the crystallization rate was 30% higher for composites with azelaic Acid attached to TiO2 particles than for composites without filler at a cooling rate of 5°C min−1. Once degraded composites containing azelaic acid were the least brittle, with a minor increment in Young’s Modulus compared to pure polylactic acid composites. When a mixture of modified titanium dioxide particles (with imidazole and either azelaic acid or pimelic acid) was used, there was a synergistic effect regarding photostability.

Effect of Ferromagnetic Exchange Interaction and Crystalline Anisotropy on a Double-Cubic Spin-½ Spin-1 Ising System with a Free Surface

In this study, we employ Monte Carlo simulations to explore the magnetic characteristics of a double-cubic spin-½ and spin-1 ferromagnetic Ising superlattice system, focusing on the impact of surface exchange coupling, anisotropy, and layer thickness. We implemented free boundary conditions along the dimension with an exposed surface. Our findings illuminate the key role played by surface exchange coupling (JAS), which significantly influences the critical temperature (Tc), underscoring its ability to strengthen ferromagnetic interactions within the system. In contrast, the compensation temperature (Tcomp) exhibits relative stability. Furthermore, we unveil the crucial influence of crystalline anisotropy on Tcomp, with higher anisotropy values leading to its augmentation, while Tc remains unaffected. Moreover, when the number of layers is increased from 11 to 21, a marked rise in Tc is observed, accompanied by a minor increment in Tcomp, particularly evident under negative anisotropy conditions.

Machine Learning Algorithms for Performance Enhancement in DCO-OFDM-Based LiFi Systems

This study describes how machine learning methods can be used to enhance the performance of LiFi (light fidelity) systems that are based on DCO-OFDM (direct current bias optical orthogonal frequency division multiplexing). LiFi, a rapidly developing technology that uses light for wireless communication, has to contend with issues like channel impairments and signal interference. This work investigates several machine learning strategies to address these problems and improve the DCO-OFDM LiFi systems' overall performance. It is determined how well various machine learning techniques perform in terms of improving system parameters, decreasing latency, and raising throughput by analyzing real-world data and simulation studies. Various sorts of symmetrical recurrence division multiplexing (OFDM, for example, DC one-sided optical OFDM (DCO-OFDM), are utilized in light devotion (LiFi). A critical DC predisposition in DCO-OFDM brings about optical power failure, while a minor inclination increment cutting commotion. In this manner, it's essential to decide the appropriate DC predisposition level for DCO-OFDM. This examination finds the ideal DC-predisposition an incentive for DCO-OFDM based LiFi frameworks utilizing machine learning (ML) algorithms. To do this, a MATLAB device is utilized to create a dataset for DCO-OFDM. Thusly, Python writing computer programs is utilized to apply machine learning methods. ML is used to recognize the basic DCO-OFDM qualities that influence the ideal DC predisposition. Here, it is exhibited that the base, greatest, and standard deviation of the bipolar OFDM signal, as well as the size of the heavenly body, decide the ideal DC inclination.

Ab Initio Driven Exploration on the Thermal Properties of Al-Li Alloy.

Al-Li alloys are feasible and promising additives in advanced energy and propellant systems due to the significantly enhanced heat release and increased specific impulse. The thermal properties of Al-Li alloys directly determine the manufacturing, storage safety, and ignition delay of propellants. In this study, a neural network potential (NNP) is developed to investigate the thermal behaviors of Al-Li alloys from an atomistic perspective. The novel NNP demonstrates an excellent predictive ability for energy, atomic force, mechanical behaviors, phonon vibrations, and dynamic evolutions. A series of NNP-based molecular dynamics simulations are performed to investigate the effect of Li doping on the thermal properties of Al-Li alloys. All calculated results for Al-Li alloys are consistent with experimental values for Al, ensuring their validity in predicting Al-Li interactions. The simulation results suggest that a minor increment in the Li content results in a slight change in the melting point, thermal expansion, and radical distribution functions. These three properties are associated with the lattice characteristics; nonetheless, it causes a substantial reduction in thermal conductivity, which is related to the physical properties of the elements. The lower thermal conductivity allows heat accumulation on the particle surface, thereby speeding up the surface premelt and ignition. This provides an alternative atomic explanation for the improved combustion performance of Al-Li alloys. These findings integrate insights from the field of alloy material science into crucial combustion applications, serving as an atomistic guide for developing manufacturing techniques.

Behavior analysis of Low-Heat Rejection engine powered by biodiesel under varied exhaust gas recirculation ratios

ABSTRACT The key focus areas of the internal combustion engine architecture are energy effectiveness and greater thermal efficiency since 1/3 of the produced heat energy vanishes on the way to the atmosphere and the coolant. Experiments have looked into the viability of using tamanu biodiesel in a thermally insulated diesel engine. The engine was first put through its paces on regular diesel fuel as a comparison baseline. After that, the piston, exhaust, intake valve and cylinder head surfaces were coated with partially stabilized zirconia (PSZ) to act as thermal insulation for the engine. The engine coating was developed to improve the efficiency of the engine’s use of biodiesel blends by decreasing heat loss through the chamber walls with a thickness of 200 micrometers (µm). In addition, mixes of Tamanu biodiesel with diesel fuel were tested, including B10, B20, B30, and B100, to examine how these mixtures would influence the performance of the ceramic-coated low heat rejection (LHR) engine compared to the performance of the base diesel engine. Additionally, the impacts of different exhaust gas recirculation (EGR) ratios on the operation of biodiesel-powered LHR engines were analyzed. The zirconia insulated LHR engine running on B20 performed the best, with a thermal efficiency of 28.57% and a brake specific energy consumption that was considerably lower than that of the baseline diesel engine. In addition, the LHR engine for B20 reduces carbon monoxide (CO) and smoke emissions by 17% and 21.4%, respectively, compared to the B20-powered base diesel engine, although nitrogen oxide (NOx) emissions slightly increase. However, the addition of 15% EGR to the B20-LHR engine produced a minor increment in hydrocarbon (HC), CO and smoke emissions, corresponding to 19.7% and 25.4%, respectively. By implementing 15% EGR with B20-LHR, the NOx level is reduced by 25.4% due to diluting the air-fuel mixture. The combination of 15% EGR with B20 for a thermal barrier-coated engine offers significant improvement by increasing engine performance and reducing emission characteristics.

Densification and microstructural correlation with thermo-mechanical strength of TiO2-doped (Al1-xCrx)2O3 (x=0.1, 0.3) solid solution ceramics

In this work, TiO2-doped (Al1-xCrx)2O3 (x = 0.1, 0.3) ceramics were prepared in the range of 1600 °C–1700 °C under a slightly reducing atmosphere. The lattice parameter calculations only showed a minor increment with TiO2 doping, implying a meager solid-solubility limit (also detected by EDS semi-quantification). The grain size of (Al1-xCrx)2O3 is directly proportional to the TiO2 amount and sintering temperature. Beyond the TiO2 solid solubility limit, exaggerated grain growth and excessive pore formation were observed at higher sintering temperatures. The highest flexural strengths were observed without TiO2 at a higher sintering temperature and with 1 wt% TiO2 at lower sintering temperatures. However, higher TiO2 inclusion has deleterious effects on flexural strengths, as the failure occurs via a combined effect of porosity and larger grains.

The effectiveness of Ni microalloying on the microstructure and mechanical properties of low temperature In-35 wt%Sn/Cu solder joint

The effects of 0.05 wt%Ni additions on In-35 wt%Sn (In–35Sn) alloy on the ex-situ interfacial reactions, in-situ microstructures formation during solidification, and mechanical properties during reflow soldering on Cu substrate were systematically studied. Reaction of In–35Sn with Cu resulted in the formation of two intermetallic Cu3(Sn,In) layers were found at the interface. When Ni is added, Ni is participated in the interfacial (Cu,Ni)3(Sn,In) layer formed at the In–35Sn-0.05Ni/Cu interface, causing the morphology of the IMC layer at the solder side to become more refined. Adding Ni resulted in the degree of undercooling In–35Sn decreasing close to zero. The in-situ real-time synchrotron x-ray imaging confirmed that the presence of Ni is responsible for the spontaneous β-In3Sn grain nucleation and formation of equiaxed grain in the solder joint. The grain refinement on the (Cu,Ni)3(Sn,In) IMC layer in In–35Sn-0.05Ni/Cu solder joint leads to minor increment in the shear strength. This study demonstrated the effectiveness of Ni microalloying in low temperature In–35Sn/Cu solder joint in modifying the β-In3Sn dendrite growth at the bulk solder and the microstructure refinement at the interface of the solder joints, which could potentially enhance the overall joint strength.

Experimental evaluation on behavior of poly propylene fiber-reinforced concrete containing Poly Carboxylate Ether and E205 additives

Corrosion is a critical challenge that reinforced concretes are facing that need to be addressed considering environmental circumscriptions. This research investigates various characteristics of polypropylene fiber-reinforced concrete experimentally. Six contents of chemical admixtures are investigated regarding rapid chloride permeability, water absorption, electrical resistivity, and compressive strength. Moreover, quantitatively, the energy-dispersive X-ray microanalysis is employed to specify the cementitious matrix’s chemical compositions. Correspondingly, the cementitious matrix’s chemical mechanism is analyzed by utilizing X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and X-ray Fluorescence (XRF) analysis methods. The results indicate that a minor increment in the content of chemical admixtures decreases chloride permeability, while an increase results in an electrical resistivity up urge. Furthermore, the experimental results demonstrate that specimens with polypropylene fiber and polycarboxylate ether perform better than specimens containing polypropylene fiber and E205 in compressive strength. It has been discovered that specimens, including Poly Carboxylate Ether, demonstrated lower water absorption than the levels observed in specimens with E205. According to test results, it can be concluded that the durability and compressive strength of fiber reinforced concrete with polypropylene fibers are increased by the addition of chemical admixtures. • Adding polycarboxylate ether and E 205 to PPFRC, increases the concrete’s resistance. • Polycarboxylate ether and E205 reduce cracks in PPFRC. • Adding polycarboxylate ether and E205 to PPFRC reduces concrete water absorption.

Effect of addition of fuel additive in diesel with hydrogen on combustion duration

Hugh energy demand in all countries caused expeditious depletion of conventional resources of energy. The adverse effect of unregulated utilization of conventional energy sources resulted into lack of stock left and the emission of harmful pollutants into the environment. There is a need for optimized utilization of these resources and to develop new alternative sources of energy to conserve them for future generation. Dual fuel technology is a prominent method to execute for efficient combustion and healthy emission compared with conventional ones. The use of fuel additives in diesel could significantly enhance the fuel properties, promote combustion and reduce harmful emissions. Hydrogen, on the other side, is a clean and carbon free source of energy. Due to its high energy share and availability, it can be utilized in dual fuel engine for optimized emissions and performance. In the present study, tri-ethylene glycol mono methyl ether (TEGMME) as a liquid fuel additive in diesel has been utilized along with hydrogen in dual fuel approach. A four stroke, single cylinder, compression ignition diesel engine was modified to operate in dual fuel mode for the experiments. A fixed speed of the engine was maintained at 1500 rpm was maintained while the compression ratio was fixed to 18. After the experimental trials for the load range of 2–70 %, the results data were analyzed. The effects of the addition of fuel additive and hydrogen on combustion duration were studied. With the substitution of TEGMME in diesel, decrement in combustion duration was observed up to 30 % of load, while combustion duration was increased with increase in load. Hydrogen substitution resulted into increment in combustion duration with increase in load, while with the increment in H2 substitution, reduction in combustion duration at each load was observed. The combined effect of substitution of TEGMME in diesel along with hydrogen was observed for the entire load range. In these cases, minor increment in combustion duration was found at low load, while at high load it was incremented considerably.

A New ϵ-Adaptive Algorithm for Improving Weighted Compact Nonlinear Scheme with Applications

To improve the resolution and accuracy of the high-order weighted compact nonlinear scheme (WCNS), a new ϵ-adaptive algorithm based on local smoothness indicators is proposed. The new algorithm introduces a high-order global smoothness indicator to adjust the value of ϵ according to the local flow characteristics. Specifically, the algorithm increases ϵ in smooth regions, which can help cover up the disparity in smoothness indicators of sub-stencils and make the nonlinear scheme approach the background linear scheme. As a result, optimal order accuracy can be achieved in smooth regions, including critical points. While near discontinuities, the algorithm decreases ϵ, thereby strengthening the stencil selection mechanism and further attenuating spurious oscillations. Meanwhile, the new algorithm makes nonlinear schemes scale-invariant of flow variables. The results of approximate dispersion relation (ADR) show that the new algorithm can greatly reduce spectral errors of nonlinear schemes in the medium and low wavenumber range without inducing instability. Numerical results indicate that the new algorithm can significantly improve resolution of small-scale structures and suppress numerical oscillations near discontinuities with only a minor increment in computational cost.

Performance Assessment of a Single-Cylinder Diesel Engine with Diesel and Waste Cooking Oil Blends Preheated by Engine Exhaust Gas

The present work explains the engine performance using waste cooking oil (WCO) blended with diesel. The viscosity of WCO can be reduced to be comparable with diesel by preheating at 90°C and thus improves the engine combustion efficiency. For the purpose of preheating, a shell and tube heat exchanger were designed. The optimized tube and shell diameters of the heat exchanger were estimated as 17 and 460 mm, respectively. Pressure drops in tube and shell sides changed from 28.40 - 27.40 Pa and 0.025 - 0.1 Pa respectively. Flue gas energy contents varied from 4000 W to 16000 W at the mass flow rate of 0.03-0.08 kg/s. Useful energy gained by the heat exchanger for waste cooking oil preheating varied from 1200-5500 W at 1200-3000 rpm. Kinematic viscosity for WCO was 51.85 cSt and it changed to 7.55 - 17.5 cSt for blends of 10 - 30% with diesel at 40°C. As the blending % of WCO with diesel increased, there was a minor drop in brake power because of lower calorific value of the mixture. There was a minor increment of torque because of preheating. Preheated fuel blends injection into the cylinder facilitated better fuel efficiency. Minimum and maximum values of exhaust gas temperature were 345°C and 385°C at 1200 and 3000 rpm of engine speeds respectively.

Effect of Brine fermented Pickling to Physicochemical, Anti-nutritional, and Microbiological Attributes of Pickled gboma Eggplant (Solanum macrocarpon)

Gboma eggplant (Solanum macrocarpon) has low calorie, high phenolic and antioxidant, excellent dietary fibre and mineral content. Besides healthy effects, gboma eggplant also contained numerous anti-nutrients unbeneficial for human health. Due to high moisture content, gboma eggplant was highly perishable during post-harvest. This research observed the changes of nutritional proximate, mineral contents, acidification indexes, anti-nutrients, phytochemical and antioxidant properties, texture profiles, microbiological characteristics of both raw and pickled gboma eggplant. Gboma eggplant fruits were soaked in clean water for 2 minutes before cutting their calyx lobes. The pre-treated fruits were submerged in sterilized brine (5% salt) for 8 days. Periodically, pickled samples were taken to examine physicochemical, anti-nutritional, and microbiological attributes of pickled gboma eggplant. Results showed that nutritional proximate of moisture, ash, protein, fat, fibre, carbohydrate was varied slightly during fermentation. There was a decreasing trend of moisture and carbohydrate; meanwhile, there was an increasing trend of ash, protein, fibre during 8 days of fermentation. There was no significant difference of fat during pickling. There was a minor increment of mineral contents in all samples. There was accumulation of phenyllactic acid, ascorbic acid content and titratable acidity with exception of pH. Anti-nutrient contents like tannin, phytate, oxalate, steroidal glycoalkaloid greatly decreased in raw and pickled eggplant. Remarkable increments of total phenolic, flavonoid, DPPH free radical scavenging and FRAP ferric reducing antioxidant of raw and pickled eggplant was presented. Texture profiles of hardness, crispness, fracturability, crunchiness revealed a minor reduction of sensory scores during 8 days of fermentation. Lactic acid bacteria, Bacillus significantly proliferated; meanwhile, Micrococcus and S. aureus were absolutely retarded in pickled eggplant. Yeast and fungi increased in the first 4 days and decreased afterwards. There was no significant difference of proximate compositions; mineral contents; phenyllactic acid, ascorbic acid content, pH and titratable acidity; anti-nutritional contents; phytochemical and antioxidant properties; texture profile (sensory score); microbiological load (with exception of S. aureus) between pickled gloma eggplants at day 6th and day 8th of fermentation. At a quick glance, the length of fermentation could be shorted to 6 days instead of 8 days. However, at the 6th day, S. aureus load was still presented at 0.33±0.01 log CFU/g. The fermentation should be lasted to 8th day so that S. aureus load could be dropped down to zero to ensure microbial food safety. Raw gboma eggplant should be fermented in 8% brine solution for 8 days to obtain the best physicochemical, anti-nutritional, and microbiological properties of pickle. Findings of this research suggested that fermentation pickling would be an appropriate approach to improve nutritional, physicochemical and functional criteria while controlling toxic chemical residues, retarding the growth and proliferation of spoilage and pathogen microorganisms.

Individualized PID tuning for maintenance of general anesthesia with propofol and remifentanil coadministration

In this paper we propose a methodology for a patient-individualized tuning of the parameters of a proportional–integral–derivative (PID) controller that regulates the depth of hypnosis in the maintenance phase of general anesthesia. In particular, we consider a PID controller employed in a closed-loop multiple-input–single-output (MISO) control system for propofol and remifentanil coadministration. Simulation results show that the approach provides an increased robustness with respect to both intra-patient and inter-patient compared to a population-based tuning. This is obtained at the cost of a slight decrement of the controller bandwidth that causes a minor increment of the time required to reject disturbances.

Community structure and ecosystem carbon stock dynamics along a chronosequence of mangrove plantations in China

Mangrove plantations exhibit a high potential for biomass carbon sequestration, however, their effects on soil organic carbon (SOC) accumulation remains unclear. We examined the dynamics of community structure and ecosystem carbon accumulation along a chronosequence of Sonneratia apetala plantations on Qi’ao Island, China. To reveal the self-thinning pattern of S. apetala plantations, 114 quadrats were randomly established in the S. apetala plantations. Four quadrats were selected for soil sampling from differently-aged (4, 9, and 15 years) S. apetala plantations, a 15-year-old S. apetala + Bruguiera gymnorrhiza plantation and a 40-year-old mature Kandelia obovate community. We found that the self-thinning process happened in these S. apetala plantations. The vegetation biomass was found to significantly increase with forest age and the 15-year-old S. apetala and 15-year-old S. apetala + Bruguiera gymnorrhiza plantations had similar total biomass as the 40-year-old K. obovate community. Notably, SOC content and stocks only showed a minor increment along the chronosequence of S. apetala plantations, and SOC stock of the 15-year-old S. apetala community was less than 60% of that of the 40-year-old K. obovate community. The 15-year-old S. apetala + B. gymnorrhiza community had a similar biomass value as the 15-year-old S. apetala community, but the former community had a significant higher SOC stock than the latter. Biomass increment and SOC accumulation are unsynchronized with mangrove plantation development, and monospecific mangrove plantations may not be able to significantly accelerate SOC sequestration in the early plantation stage. Multi-specific plantations may facilitate SOC accumulation more than monospecific plantations.

Introspection Into Reliability Aspects in AlGaN/GaN HEMTs With Gate Geometry Modification

Reliability enhancement of AlGaN / GaN HEMT is a significant thrust area due to rapidly improving material and processing technology. In this paper, a detailed analysis of gate-shaped AlGaN / GaN HEMT with field plate is presented. Although AlGaN / GaN HEMT with field-plate is well known, its blending with gate-shaping leading to a more robust and reliable behaviour is described in this paper. It is observed that the threshold voltage and transconductance invariably remain constant for various combinations of gate-shaped and field plate placements. The threshold voltage for all the devices are found to be - 5.8 V. The peak transconductance for the devices without field plate and with field plate is ~ 0.16 S/mm and ~ 0.15 S/mm, respectively. Apart from leakage current, the electric field also gets mitigated for both gate-shaped and field-plated devices by ~ 45% and ~ 68%, respectively. The moderation in electric field further assists in the reduction of electron temperature for gate-shaped and field-plated structures by ~ 12% and ~ 85%, respectively. Additionally, breakdown voltage increases for the gate-shaped devices to 133 V as compared to 120 V of conventional devices without field plate. Significant reduction in leakage current, electric field, and electron temperature is accompanied by a minor increment in capacitance for the field-plated structure, hence, the proposed structure is expected to enhance reliability of the device. Thus, it is anticipated that the proposed devices with enhanced reliability would be a step ahead of conventional devices and would find major applications in high power domain.

Echocardiographic parameters associated with recovery in heart failure with reduced ejection fraction.

The study aims to determine the clinical and echocardiographic parameters of patients with recovered heart failure (HFrecEF). Sixty-seven patients (cases) were identified as heart failure with recovered ejection fraction (HFrecEF), defined as improvement in EF≥10%. Sixty-nine patients (controls) were randomly selected by convenience sampling with no or <10% improvement in EF (HFrEF non-recovered). The mean interval between baseline and follow-up echocardiography was 10.5months in cases and 11.2months in the control group. HFrecEF showed a 22.7% improvement in mean ejection fraction, and HFrEF non-recovered group also showed a minor increment of 5.5%. HFrecEF patients were significantly younger (49.51 vs 57.54years, P .001) with non-ischemic cardiomyopathy (86.6% vs 52.2%). Patients with HFrecEF had significantly less left ventricular end-diastolic and end-systolic volumes (LVEDV: 162.51mL vs 208.54mL, P<.001; LVESV: 119.81mL vs 157.13mL, P<.001) and index left atrial volume (37.66mL vs 47.09mL, P<.001) than patients with non-recovered EF. The right ventricle (RV) and inferior vena cava were significantly dilated with higher mean tricuspid annular plane systolic excursion (TAPSE) among patients with HFrecEF than HFrEF non-recovered. Based on univariate analysis, younger age, non-ischemic etiology, LVEDV, LVESV, deceleration time, better TAPSE, dilated right ventricle, dilated IVC, and smaller left atrial volumes were found significant, but on multivariate logistic regression model only left ventricle end-diastolic volume, left atrial volume, and TAPSE were linked to the recovery of ejection fraction.

Hardware-Efficient 2D-DCT/IDCT Architecture for Portable HEVC-Compliant Devices

Low power hardware acceleration cores for integration into real-time High Efficiency Video Coding (HEVC) codec for smartphones, tablets, camcorders, and televisions are in great demand. This need motivates one for an efficient realization of Discrete Cosine Transform (DCT) and Inverse-DCT (IDCT) for HEVC. This paper presents an algorithm to calculate the required minimum number of low-frequency DCT-output/IDCT-input coefficients for 4, 8, 16, and 32-point DCT/IDCT in HEVC, such that there is a slight decrease in peak-signal-to-noise-ratio (<; 0.15 decibel) and a minor increment in bitrate (<; 1.5%) as compared to the reference HEVC-Test-Model (HM) Software. However, the encoding time gets reduced at most by 17.95% for Class-A type sequences, while reporting mean-squared-error and structural-similarity of 1.42 and 0.9913, respectively for 4K ultra-high-definition videos. Moreover, HEVC-compliant computationally efficient architectures are introduced for n-point DCT/IDCT. The presented flexible Transpose Memory architecture uses only sixteen random-access-memories to support all transform-unit sizes in HEVC. The proposed two-dimensional DCT/IDCT architecture can process up to 288@$4K$ frames-per-second, and it consumes the minimum power, energy, and area of 11.23 milliwatts, 2.34 picojoules, and 120 kilo-gate-equivalents, respectively. Such design with low power, area, and energy features can be included in a real-time HEVC codec for HEVC-compliant consumer electronic devices.

Structure, microstructure and surface of Nd3+-doped mesoporous anatase-phase TiO2

We prepared nanocrystalline mesoporous anatase-phase TiO2 doped in the range from 0.0 to 1.0 at.% of Nd3+ by the reverse microemulsion method (RMM). The analysis of electron microscopy of the nanocrystal revealed a truncated-tetragonal bipyramidal shape and agglomerates of spheroidal nanoparticles with inter-particle porosity. The inductively coupled plasma (ICP) technique corroborated the doping concentrations. The analysis of structural parameters by the Rietveld refinement technique indicated the variation of Ti–O(1) and Ti–O(2) bond lengths, suggesting the Nd3+ insertion in the lattice. The microstructural analysis by the Williamson–Hall plot (WH) and whole powder pattern fitting (WPPF) revealed that the doping addition has a slight inhibition effect on the crystal size (6–8 nm) with a minor strain increment. The surface analysis from N2 adsorption/desorption isotherms showed that the incorporation of the dopant in low amounts improved the mesoporous structure stability, increased the diameter of opening pores, and changed the pore structure network. The XPS analysis of the chemical states on the surface suggests that the Nd3+ presence changed the Ti 2p region and the presence of the two chemical states of oxygen (OI and OII).

Investigation on effects of the exhaust emission characteristics of diesel engine fuelled with mahua oil methyl esters and its blends with diesel

Diesel engines are deliberately known for environmental pollution caused by exhaust emissions and are liable for many health issues further more. Emissions of diesel exhaust might lead to cancer, irritate the eyes, affects the nose, throat and lungs. Biodiesel is an eco-friendly and typical alternative fuel which is produced from vegetable oils through transesterification technique. Biodiesel has its own several advantages than the conventional diesel says decreased in carbon monoxide (CO), unburnt hydrocarbon (HC) and particle matter (PM) emissions, and having fuel properties which are similar to conventional diesel for its easier use in diesel engines. The outcomes demonstrated that the production of lesser CO and HC emission using biodiesel. Nevertheless, a minor increment in NOx emission was noticed for mahua oil methyl ester blends. Brake Specific Fuel Consumption (BSFC) for methyl ester blends was raised as compared to diesel. The combustion analysis exhibited a significant rise in combustion pressure and heat release rate with smaller ignition delay and extended combustion period. From the investigation, it could be said that the effects of mahua oil methyl esters and its blends on diesel engine when compared to conventional diesel ultimately minimizes the health effects of biodiesel exhaust exposure.

Dynamic fracture propagation model for oriented perforation steering fracturing in low permeability reservoir based on microelement method

Oriented perforation steering fracturing technology with the purpose of enlarging fracture extension scale and increasing reservoir reconstruction volume is a common method for stimulating and reforming low permeability oil and gas reservoirs. Accurate prediction of the fracture deflection trajectory is the key to successful implementation of this technology. Based on the relevant theories of elastic fracture mechanics and the microelement method, a prediction model for the fracture deflection trajectory of steering fracturing is established by comprehensively considering the influences of horizontal in situ stress difference, perforation parameters, injection parameters and formation mechanics parameters. The model completes the cyclic iteration calculation between the minor increment and the propagation direction angle of the crack tip using the calculation program compiled by Visual Basic and realizes the simulation of the dynamic propagation of steering fractures. Taking the tight sandstone reservoir of the Shihezi Formation in Linxing block as an example, the differences between the hydraulic fracture trajectory calculated by this model and the extended finite element model and the micro-seismic monitoring values in the fracturing field were compared, and the influence of various factors on the deflection distance of the hydraulic fracture trajectory were studied. The results show that, compared with the XFEM model, the hydraulic fracture trajectory simulated by this model has better matching with the micro-seismic monitoring results. The deflection distance decreases negatively logarithmically with increasing horizontal in situ stress difference and increases linearly with increasing fracturing fluid displacement and viscosity. The larger the perforated angle, the longer the deflection distance, and the length of perforation has little effect on the deflection distance. The model and conclusions are significant to further understand oriented perforation steering fracturing.