Spring Applications Research Articles

Effect of heat treatment on phase transformation behavior, tensile fracture mechanism and spring application characteristics of 631 stainless steel

This study focuses on enhancing the mechanical properties of 631 stainless steel through heat treatment for spring applications. 631 stainless steel (17–7PH), can achieve increased hardness and mechanical properties, offering high strength and hardness suitable for use in aerospace, chemical, and automotive industries. Heat treatment was recommended as one of the best ways in this regard; hence, the effects of temperature and time on the microstructure, mechanical, and corrosion properties of 631 stainless steel have been studied. This research conducted a series of heat treatments on 631 stainless steel, included solid-solution treatment, CH900, RH950, and TH1050 processes to modify the temperature holding period and the degree of undercooling of phase transformations. The study explored the microstructure and mechanical properties of each heat treatment, including spring tests. The results indicate that solid-solution treatment has no significant contribution to hot-rolled 631 stainless steel, whereas two-stage aging is able to conspicuously improves material hardness and mechanical performance. Quenching in 0°C ice water (increasing the degree of undercooling) can elevate hardness to approximately HRC40. After a two-stage aging heat treatment, 631 stainless steel possesses excellent strength and corrosion resistance. Spring test results show a K value of 1.1 kg/ mm, indicating its potential application.

Spring-Assisted Cranioplasty in Unicoronal Synostosis: Analysis of Outcomes

Background: Spring-assisted cranioplasty and successful long-term outcomes for sagittal synostosis has been well described in recent literature. However, there is a paucity of data regarding the application of springs to unicoronal synostosis. Unicoronal synostosis (UCS) presents unique challenges in its causation of skull base scoliosis and orbital asymmetry. Many surgeons feel that the fronto-orbital advancement and vault remodeling is the most effective and reliable strategy to counteract these changes. Here we present our experience and outcomes with spring cranioplasty for unicoronal synostosis. Materials and methods: A retrospective review of non-syndromic unicoronal synostosis patients undergoing spring-assisted cranioplasty was performed. Preoperative and postoperative intracranial volume (ICV), orbital volume (OV), orbital height (OH), orbital width (OW), midface twist (MFT), and skull-base twist (SBT) were measured from DICOM CT data. Analysis was performed with Materialize software (Leuven, Belgium). Paired t-tests were performed using Excel. Results: Ten patients (5 females, 5 males) had springs placed at 100.1 days (avg). Average ICV: preop: 608.2 ± 101.4 cc, postop: 995.2 ± 166.1 cc. Differences in orbital volume and height in the preop affected orbit versus non-affected orbit was significant ( P = .01, P ≤ .001 respectively) whereas no significant difference between the two sides postoperatively was observed ( P = .19, P = .58 respectively). Average preop MFT was 81.1 ± 2° and postop was 87.6 ± 2.6° and preop SBT was 171.9 ± 2.7° and postop was 177.6 ± 2.6°; both showing significant improvement after spring cranioplasty (both P ≤ .001). Conclusion: Our experience and early outcomes with spring cranioplasty for UCS demonstrates that when used in younger patients (<5 months) cranial springs can be a safe and effective strategy to minimize skull base scoliosis, facial scoliosis, and orbital asymmetry, as well as increase intracranial volume. Although long-term data needs to be assessed, we are optimistic that early correction of cranial base scoliosis will translate to stable results as patients reach dentoskeletal maturity.

Application of conical spring to maintain tuning of mass damper for wave-induced vibration control of offshore jacket platform subjected to changes in natural frequency

Offshore jacket platforms are situated in challenging environmental conditions and often experience changes in mass and stiffness, resulting in alteration in its dynamic properties. The tuned mass damper (TMD), known for its effectiveness in vibration control, has been earlier studied for implementation in jacket platforms. However, it is sensitive to tuning and would suffer a performance loss if the structural frequency undergoes modification. This can be overcome by connecting the damper mass to the structure by a conical spring that exhibits multilinear behaviour. This allows the TMD to remain tuned to different values of the structural frequency. In this study, the jacket platform is modelled as a multi-degree-of-freedom (MDOF) system, and the performance of the designed TMD with conical spring (TMD-C) is investigated in both frequency and time domain. Two possible variations in the fundamental period of an example jacket structure are considered and the results of wave-induced vibration control of deck responses achieved by the TMD-C are compared with those by the conventional TMD. Results indicate that despite being a passive device, the TMD-C can maintain the desired tuning to the structural frequency and thereby outperforms the conventional TMD in the reduction of the deck responses.

Seismic performance and design of an innovative structure with controlled rocking shear wall using ring springs

The application of ring springs in civil engineering, aimed at improving the seismic behavior of structures, has been largely overlooked despite their many advantages. These springs are highly durable, heat-resistant, low-maintenance, and self-centering, meaning that they withstand large deformations while always returning to their original state. Structures equipped with properly designed ring springs survive earthquakes without suffering major damage or plastic deformation, making them an excellent investment in terms of both economic efficiency and sustainable resource use. This paper explores a new use for ring springs in earthquake-resistant structures, with a focus on their implementation into controlled rocking shear walls. A parametric study utilizing the Non-Linear Time History Analysis method was conducted on a simplified model to investigate the rocking behavior and derive a design methodology based on the obtained results. A comparative study was conducted on elastic, non-linear, and rocking shear walls to demonstrate the feasibility and design principles of the rocking systems. Furthermore, the results of the comparative studies provided evidence supporting the efficacy of incorporating ring spring dampers into the rocking systems. The controlled rocking shear wall demonstrated elastic behavior during seismic loading, indicating that the addition of ring spring dampers was effective in enhancing its performance. On the other hand, the conventionally designed numerical model exhibited nonlinear behavior at its base. The developed design procedure ultimately enables the practical application of controlled rocking shear walls using ring spring dampers in earthquake engineering.

Late fall synthetic acaricide application is effective at reducing host-seeking adult and nymphal Ixodes scapularis (Ixodida: Ixodidae) abundances the following spring.

Based on increases in reported cases of tick-borne illnesses, expanding ranges of native ticks, and repeated documentation of arrivals of nonnative tick species, there is a clear need for their effective management in the United States. Synthetic acaricides have proven efficacious in tick management, but real/perceived negative impacts to the environment and nontarget, beneficial insects must be addressed. We sought to determine whether late fall synthetic acaricide application, when most susceptible beneficial insects are presumably dormant or have migrated, could effectively manage host-seeking spring Ixodes scapularis Say abundances as compared to traditional spring application. We compared results of delivery of Demand CS (lambda-cyhalothrin) via truck-mounted high-pressure spray and powered backpack blower as well as delivery of granular Demand G to experimental control (water) in peridomestic habitats in fall 2021, spring 2022, and combined fall 2021/spring 2022. High-pressure fall delivery of Demand CS and backpack delivery of Demand G significantly reduced host-seeking adult I. scapularis abundances within-season and the following spring combined by 100% and 94%, respectively. No host-seeking nymphal I. scapularis were documented in spring after fall only, spring only, or fall and spring combined delivery of Demand CS via high-pressure or powered backpack blower. No adult I. scapularis were documented at any time posttreatment on locations that received high-pressure delivery of Demand CS. We conclude that high-pressure delivery of Demand CS in late fall successfully eliminated multiple stages of host-seeking I. scapularis through the following spring while likely limiting exposure of beneficial insects to synthetic pyrethroids.

Pasture productivity benefits from strategic urease and nitrification inhibitor use are limited in rainfed temperate dairy pastures of southern Australia

Abstract Introduction Urea is the most commonly used nitrogen (N) fertiliser on Australian dairy pastures, but has low N use efficiency due to high loss potential. Urease and nitrification inhibitors can be used to reduce these losses, however, their efficacy is highly variable and the reported impacts on productivity are inconsistent, with assessments often made using a single inhibitor across all seasons. Research question We examined the effectiveness of two commonly used inhibitors, the urease inhibitor N-(n-butyl) thiophosphoric triamide (NBTPT) and the nitrification inhibitor 3,4-Dimethylpyrazole phosphate (DMPP) applied in a strategic program, on pasture responses to urea (U) fertiliser, and fertiliser N use efficiency in a temperate dairy pasture in Southern Australia. Materials and Methods Pasture productivity, N uptake, agronomic N use efficiency (NUAE), 15N fertiliser recovery and soil mineral N were monitored. The nitrogen was applied in the urea form at rates of 160, 320, 480 and 640 kg N ha−1 yr−1 Results and Conclusions The majority of the plant N (64%-85%), assessed over autumn and spring growth periods using 15N, was derived from mineralised soil organic matter (SOM). Neither of the inhibitors significantly altered pasture production or NUAE, most likely because of the major role of SOM in supplying N to plants, and because much of the applied 15N (up to 55%) was retained in the soil (0-40 cm depth) due to microbial immobilisation. Uptake of fertiliser N was highest, up to 29% of applied N, immediately following fertiliser application and then was substantially reduced over subsequent months, reflecting low levels of mineralisation of the previously immobilised N. The total loss of applied 15N was greater following autumn applications of N than spring applications, being 14% - 42% and 2% - 7% respectively and was attributed to volatilisation occurring primarily in autumn, with minimal leaching and denitrification predicted under the experimental conditions.

Impact of novel herbicide based on synthetic auxins and ALS inhibitor on weed control.

Delayed sowing of winter cereals or unfavorable weather conditions in autumn may make it impossible to carry out herbicide treatment in autumn. In such cases, weed control should be started in the spring. During this time, the plantation should be protected as effectively as possible because the weeds are at an advanced stage of growth. Therefore, they are less sensitive to applied herbicides. In the treatment, it is worth using a mixture of different mechanisms of action. Studies were conducted to evaluate the effectiveness of a band of tribenuron-methyl, and MCPA applied as soluble granules in spring control of dicotyledonous in winter cereals. The biological efficacy of herbicides was estimated in the 25 field experiments on winter cereals in Poland. Postemergence, a spring application of tribenuron-methyl + MCPA, effectively controls the majority of weed species present in spring: Anthemis arvensis, Brassica napus, Capsella bursa-pastoris, Centaurea cyanus, Lamium purpureum, Matricaria chamomilla, Tripleurospermum inodorum, Stellaria media and Thlaspi arvense. Satisfactory control was confirmed for Veronica persica, Viola arvensis, and Galium aparine. Tribenuron-methyl with MCPA is recommended for application to winter cereals in spring. To prevent the development of resistance in weeds, it is advantageous to combine two active substances.

Power Generation Enhancement through Latching Control for a Sliding Magnet-Based Wave Energy Converter

A Surface-Riding Wave Energy Converter (SR-WEC) featuring a sliding magnet inside a pitching cylindrical hull is investigated as an easily deployable small power device to support small-scale marine operations. This study extends the earlier development of the system by authors to enhance power performance through the application of end spring and latching control. The inclusion of springs at the tube’s end enhances the magnet release and travel speeds as well as the average power output compared to systems without them. Further improvement of power output can also be achieved by employing optimal latching control. We introduced constant-angle and variable-angle unlatching strategies to determine optimal parameters in combination with passive and reactive power take-off (PTO) controls to assess their effectiveness. The optimized latching control and end spring can increase 60–80% more power output compared with the case without them under certain PTO damping. Additionally, we discussed the effects of limiting peak powers and associated energy leaks with latching.

Enhancing Mechanical Properties of Carbon–Silicon Steel through Two‐Stage Quenching and Partitioning with Bainitic Transformation: Ultimate Tensile Strength of 1875 MPa and Total Elongation of 8.03%

To achieve the desired microstructural properties, the ongoing development and innovation in new structural steels require novel thermal processing. This study aims to improve the mechanical properties of a commercial spring carbon–silicon steel by tailoring its microstructure through a process involving quenching and partitioning (Q&P) followed by bainitic transformation. A two‐stage Q&P process is proposed to generate a nanoscale dispersion of stable retained austenite and carbides within the tempered martensite and bainite microstructure. The resulting tensile properties demonstrate a yield strength of 1280 MPa, an ultimate tensile strength of 1875 MPa, and a total elongation of 8.03%. These values surpass those of conventional spring 9254 steel, highlighting the effectiveness of the thermal treatment design. Microstructure analysis reveals the presence of tempered martensite, bainite sheaves, nanoscale carbides, and aggregates of retained austenite. Moreover, the resulting body‐centered cubic matrix exhibits minimal lattice tetragonality of ≈1.0051, coupled with stable retained austenite featuring a carbon concentration of ≈3.42 ± 0.5 wt%, resulting in outstanding strength–ductility properties. These findings indicate that the proposed two‐stage Q&P process, followed by bainitic transformation, significantly enhances the mechanical properties of carbon–silicon steels, making it a promising candidate for high‐performance spring applications.

An Agronomic Efficiency Analysis of Winter Wheat at Different Sowing Strategies and Nitrogen Fertilizer Rates: A Case Study in Northeastern Poland

This study was undertaken to examine the influence of the sowing date, sowing density, and split spring application of nitrogen (N) fertilizer on plant density, tillering, yield components, and grain yields of winter wheat (Triticum aestivum L.) grown in northeastern Poland between 2018 and 2021. The experiment had a split-plot design with three sowing dates (early (3–6 September), delayed by 14 days, and delayed by 28 days), three sowing densities (200, 300, and 400 live grains m−2), and three split spring N rates (40 + 100, 70 + 70, and 100 + 40 kg ha−1 applied in BBCH stages 22–25 and 30–31, respectively). The number of spikes m−2 increased by 11% on average when winter wheat was sown with a delay of 14 days (17–20 September) and 28 days (1–4 October). The number of spikes m−2 was highest when winter wheat was sown at 300 and 400 live grains m−2. The application of 100 + 40 kg N ha−1 (BBCH 22–25 and 30–31, respectively) increased the number of spikes m−2. An increase in sowing density from 200 to 300 to 400 live grains m−2 decreased the number of grains spike−1 by 5% and 7%, respectively. Thousand grain weight (TGW) increased by 1% and 2% when sowing was delayed by 14 (17–20 September) and 28 days (1–4 October), respectively. In northeastern Poland, grain yields peaked when winter wheat was sown between 17 September and 4 October (10.52–10.58 Mg ha−1). In late-sown winter wheat, grain yields increased due to a higher number of spikes m−2 and higher grain weight. The highest sowing density (400 live grains m−2) induced a greater increase in grain yields than the lowest sowing density (200 live grains m−2) (10.25 vs.10.02 Mg ha−1). In winter wheat sown at a density of 400 live grains m−2, the increase in grain yields resulted in a higher number of spikes m−2. Grain yields peaked in response to 100 kg N ha−1 applied in BBCH stages 22–25 and 40 kg N ha−1 applied in BBCH stages 30–31 (this split N rate increased the number of spikes m−2). In turn, the highest straw yield (6.23 Mg ha−1) was obtained when the second split of N fertilizer was applied in BBCH stages 30–31 (40 + 100 kg N ha−1). Straw yields decreased significantly (by 6%) when winter wheat was sown late (early October). Delayed sowing (mid-September and early October) increased the harvest index (HI) of winter wheat by 5–7%. Split spring N application influenced grain and straw yields, but it had no effect on the HI of winter wheat.

Dodine an effective alternative to copper for controlling Venturia oleaginea, the causal agent of pea-cock eye disease, in highly infected olive trees.

A trial was carried out in central Italy in an olive orchard of cultivar Moraiolo, highly infected by Venturia oleaginea. The aim of the investigation was to evaluate the effects of autumn and spring applications of copper oxychloride or dodine to control the disease. Non treated trees were used as the control. The effects of the fungal attacks on leaves and inflorescence development confirmed the high susceptibility of the cultivar Moraiolo to the disease. The results show that in trees heavily infected, but with most of the infected leaves at the early stage of the disease (asymptomatic phase), treatments with dodine had a curative effect, with consequent reduction in the appearance of symptomatic leaves and defoliation with respect to the control or copper-treated trees. The use of dodine against the autumnal attacks of V. oleaginea allowed most of the old leaves to be maintained until the new ones had formed, which is important for the growth processes during the early part of the growing season. Overall, the results indicate that to efficiently control the pathogen using copper compounds, treatments must start soon after the beginning of the attack and be repeated in order to maintain the infection at a low level. Dodine can be efficiently used if there is a great increase in infected leaves. The use of dodine to solve particular situations and not for normal repeated use is regulated by the fact that in some countries, Italy included, protocols for integrated pest management allow only one dodine treatment/year.

Design methodology for fiber-reinforced polymer composite springs and experimental study on a volute spring

Fiber-reinforced polymer (FRP) composites are particularly suitable for spring applications due to numerous advantages like lightweight design, intrinsic damping, or chemical resistance. Although there are many studies on the properties of FRPs and even some on springs made out of these materials, there is no holistic method for FRP spring design. Therefore, this article focuses on a new approach that combines all relevant design steps. This includes a spring-related overview of requirements and associated FRP properties, as well as recommendations regarding material and spring type selection with a specialization on polymer composite volute springs. Thereupon, a mountain bike rear suspension spring was designed and produced. These carbon fiber-reinforced polymer (CFRP) lightweight spring, which weighs only half of the metal spring, was examined in static and cyclic experiments. Important results of the tests are a lower spring rate than theoretically expected as well as a loss of stiffness of the spring of about 25% after 25,000 full deflections just before failure. Downhill riding tests were carried out and showed comparable driving characteristics as when using conventional steel springs. The research is a contribution to FRP spring design considerations as well as to extend the range of applications for composite springs, and especially volute springs, in the future.

Effects of fall-spring cement applications on soil physico-mechanical quality of seed bed and seedling emergence.

The physico-mechanical quality of the seed bed is extremely important not only for the soil air-water dynamics, but also for the germination, seedling emergence, and development of the plants. The crust layer formed after precipitation and irrigation in soils with poor structural properties is among the most important indicators of the lower seedbed quality. While there are different applications to increase the physico-mechanical quality of the seedbed, there are also cement applications that provide rapid aggregate formation and stability. The effects of cement application on the soil mechanical quality and seedling emergence of clay textured soil with poor structural characteristics were investigated in the present study. For this purpose, a total of 36 small plots with a size of 2.4 m2 were created. Cement was applied at 0.25-0.5-1 and 2% doses to 18 plots in the fall period, and to the other 18 plots in the spring period. After the treatment, soil samples were taken for analysis before the planting period and the number of seedling emergence was determined by planting the bean plant during the planting period. According to the results of the study, it was found that cement applied in two periods caused an increase in soil aggregate stability, decreased penetration resistance, modulus of rupture, and dispersion rate, and increased water holding capacity to a limited extent. On the other hand, cement application also had positive impacts on the emergence of the bean plant. The 1% dose of the spring application of cement was more effective on the determined soil structural characteristics and seedling emergence.

Effect of residue incorporation and INM on productivity of spring maize (<i>Zea mays</i>) in rice (<i>Oryza sativa</i>)-based cropping system

A field experiment was conducted during 2019 and 2020 at the research farm of Punjab Agricultural University, Ludhiana, Punjab to study the effect of integrated nutrient management (INM) on grain yield, economics, and system productivity of spring maize (Zea mays L.) under residue incorporation in a diversified cropping system. The main plot consisted of 4 treatment combinations, viz. straw removal + 100% NPK + farmyard manure (FYM) @50 t/ha; straw removal + 150% NPK; straw incorporation + 100% NPK + FYM @50 t/ha; and straw incorporation + 150% NPK, while sub-plot consisted of 3 nutrient levels (75%, 100% and 125% NPK) applied to spring maize planted in a single row and double rows on bed. The results revealed that combined application of straw incorporation + 100% NPK + FYM @50 t/ha resulted in significantly higher grain yield (80.1 and 83.6 q/ha), net returns (259.9 and 300.2 ×103 ₹/ha), benefit cost ratio (1.34 and 1.51) and system productivity (82.9 and 89.1 kg/ha/day) of spring maize and application of 125% NPK to double row on bed resulted in significantly higher grain yield (14.6%, 12.9%) and system productivity (5.4%, 4.7%) as compared to 100% NPK to single row on bed during 2019 and 2020, respectively. Residue incorporation along with INM increased grain yield, net returns, nutrient uptake and system productivity of spring maize.

Evaluation of herbicide programs for the control of knotroot foxtail [Setaria parviflora (Poir.) Kerguélen] in bermudagrass pasture

Abstract Knotroot foxtail has become more prevalent and problematic in pastures and hayfields in the southeastern United States. Gaps exist in our knowledge of which herbicide practices are best for managing this species in bermudagrass forage production. This study was conducted to determine the efficacy of various ways to control knotroot foxtail in bermudagrass with herbicide applications in autumn, postemergence (POST), with and without also applying a herbicide in preemergence (PRE), in spring. The study was a randomized complete block with a factorial arrangement of treatments and included a nontreated control for both fall and spring timings. Glyphosate at two rates (0.35 or 0.7 kg ae ha−1), nicosulfuron (0.07 kg ai ha−1) + metsulfuron (0.012 kg ai ha−1), and hexazinone (1.3 kg ai ha−1) were applied alone in the fall or followed by indaziflam (0.067 kg ai ha−1) or pendimethalin (4.46 kg ai ha−1) in the spring. Three harvests were conducted throughout the growing season to evaluate weed species (knotroot foxtail, large crabgrass, and horsenettle) and bermudagrass biomass as well as overall species composition. The combination of fall and spring treatments did not affect weed species or bermudagrass biomass. Therefore, treatment main effects were analyzed by fall or spring application timing. A spring application of either pendimethalin or indaziflam increased bermudagrass biomass compared with that of the nontreated control. However, neither PRE herbicide effectively reduced knotroot foxtail biomass compared with the nontreated control, although pendimethalin did reduce season-long knotroot foxtail composition. Spring PRE herbicides are an effective tool for forage producers, but further research is needed to identify effective herbicides and additional approaches for the control of knotroot foxtail.

On the Automated Unit Tests Generation for Java Applications using Spring Framework

This paper considers the automated unit tests generation for programs written in Java using the Spring framework. Although several test generation tools for “pure” Java applications have been developed in recent decades, the features of this framework are mostly not taken into account. However, Spring is used to develop many industrial Java applications. At the same time, the presence of Spring components in the application for which the tests are generated imposes additional requirements not only on the code analysis approaches, but also on the structure of the generated tests. The main source of the information about object types and their properties is the Spring application context. The paper proposes an instrument for analyzing the application context, that in some cases allows generating test scenarios corresponding to real program executions and avoiding excessive mocking. The full initialization of the application context does not occur during this analysis. It makes the test generation safe for user data. The proposed instrument for analyzing the Spring context has been integrated into the UnitTestBot Java automatic test generation tool. We also provide examples of tests generated for real open-source projects.

The effect of nitrogen and phosphorus fertiliser application rate and strategy on herbage production and nitrogen response in spring

Maximising herbage yield while reducing nitrogen (N) fertiliser input, particularly in spring, is essential to ensure environmental and economic sustainability on grassland farms. A plot experiment was conducted over 2 yr, comparing three different spring N application rates of 30 (30N), 60 (60N) and 90 (90N) kg N/ha using three different spring application strategies: 0:100 (S1), 50:50 (S2) or a 33:66 (S3) split across February and March, respectively. Half of the plots also received phosphorus (P) fertiliser with the first application of N at a rate of 13 kg P/ha. Nitrogen fertiliser application for the remainder of the year (April–September) was the same for all plots (23 kg N/ha/application). Both spring and cumulative herbage yields were significantly affected (P < 0.05) by N application rate; 90N had the greatest spring and cumulative herbage yield compared to 30N and 60N (10,925, 9,834 and 10,499 kg DM/ha, respectively); however, N response reduced as N application rate increased. Nitrogen application strategy had a significant effect (P < 0.05) on spring herbage yield, with S1 significantly lower than S2 and S3. Applying 13 kg P/ha in spring increased herbage yield at defoliations 2 (23 April) and 3 (15 May) (+133 and 56 kg DM/ha, respectively), relative to no application of P fertiliser, as well as increasing cumulative herbage yield (+241 kg DM/ha). The results of the current study indicate that N should be applied in early February and the strategic application of N and P during spring can increase spring and cumulative herbage yield.

SOFT WINTER WHEAT YIELD GROWN ON LEACHED CHERNOZEM OF THE WESTERN CISCAUCASIAN REGION

The article presents the results of a study in the agrocenosis of soft winter wheat to determine the effects of pre-sowing and early spring application of various forms and combinations of nitrogen, phosphorus, and potash fertilizers when growing it in the leached chernozem of the Western Ciscaucasia. The soil is characteristic of a satisfactory state of the structure, density: 1.26–1.42 g/cm3; active acidity (pH): 6.29– 6.58 pH; exchangeable (pH): 5.11–5.25 units; hydrolytic: 1.94–3.05 meq/100 g; the amount of absorbed bases: 27.5–31.2 meq/100 g; cation exchange capacity: 30.6– 33.1 meq. /100 g; the soil saturation degree with bases: 90.2%–94.3%; and humus content: 2.93%. Fertilizers improve the nutrient regime of the soil. The average supply level with mineral nitrogen, high and mobile phosphorus, and very high mobile potassium has been well-defined. It could lead to an increase in grain when applying N120P30K60 - 1.28 t/ha (or 24.1%), N120P90K20 - 1.47 t/ha (or 27.8%), and N120P90K60 - 1.53 t/ha (or 28.8%). The grain yield of soft winter wheat was 6.58, 6.77, and 6.83 t/ha, respectively. The protein content in the grain varied from 13.2% to 14.3%. The collection of protein per hectare was 870.5, 948.5, and 958.3 kg/ha for the treatments N120P30K60, N120P90K20, and N120P90K60, respectively. The protein in the control was equal to 554.9 kg/ha. Dispersion analysis of the study results showed the share of the contribution of the factor "combination of fertilizers" was 75.95%. Similarly, the data analysis of the conditions of the agricultural year and combinations of mineral fertilizers has a smaller share - 19.24%. With the introduction of N120P30K60 and N120P90K20, the payback of mineral fertilizers by increasing the yield of soft winter wheat grain is the largest - 6.10 and 6.39 kg/kg a.i. NPK, respectively.

Effect of ammonium and potassium nitrate on winter hardiness and yield of winter rye (<i>Secale cereale</i> L.)

The results of research for 3 years (2019–2021) on winter rye (Secale cereale L.) crops in the North-West region of the Russian Federation (Leningrad region) are presented. The effect of different doses and timing of ammonium and potassium nitrate application on winter hardiness and productivity of winter rye plants on the example of Volkhova and Eureka varieties was studied. The soil in the experimental fields was sod-podzolic loamy with the depth of the arable horizon of 20–25 cm. Humus content – 2.0–2.3%, pH of the salt extract – 5.2–5.5. Fertilizers were applied in dry form in the autumn one week after the emergence of the seedlings, and in the spring – at the resumption of vegetation. The studied fertilizer doses in terms of active substance for nitrogen were 0 (control), 30, 60 and 90 kg/ha. It is shown that winter hardiness of both varieties practically did not depend on the doses and timing of the application, as well as on the type of fertilizers. The maximum grain yield was shown by the Volkhova variety at a dose of nitrogen of 60 kg/ha, the Eureka variety – 90 kg/ha, with the maximum yield of the Eureka variety for all the years exceeding that of the Volkhova variety by 24.5%. Within the specified doses of nitrogen for both varieties, the best option was a single spring application of a mixture of ammonium and potassium nitrate, the worst - a single spring application of ammonium nitrate alone. On average for both varieties, potassium nitrate application in spring increased the grain yield by 16% compared to the variants where potassium nitrate was not used.

Comprehensive study of microstructure, phase transformations, and mechanical properties of nitinol alloys made of shape memory and superelastic wires and a novel approach to manufacture Belleville spring using wire arc additive manufacturing

In the present work, using wire arc additive manufacturing (WAAM), a novel approach is implemented to manufacture the Belleville spring/washer made from superelastic (SE) and shape memory (SM) Nitinol (NiTi) wires. A detailed correlation between the chemical composition, microstructure, and martensite transformation of deposited layers and their mechanical properties has been established. The energy dispersive spectroscopy (EDS) results revealed that the first track deposited using both SE and SM effect wire consisted of significant Fe constituents, which was further reduced while increasing the number of tracks. Moreover, as compared to the sample manufactured with SE effect NiTi wire (S1), the X-ray diffraction (XRD) of the sample manufactured with SM effect NiTi wire (S2) showed a secondary phase like NiTi2 along with the major NiTi (B19′ martensitic). It has been found that the presence of Ni4Ti3 precipitate in the microstructure of SE causes an enhanced superelasticity desired for the Belleville spring applications. Furthermore, the mechanical properties, microstructure, and phase transformation temperature of both S1 and S2 were investigated and compared. It was found that S2 has a finer microstructure than S1. Also, the compressive strength and hardness of S2 were higher than that of S1. In contrast, the tensile strength of the S2 was found to be lower than the S1. Regarding manufacturing the Belleville spring using WAAM, S1 showed promising mechanical and martensitic transformation results.