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Inappropriate rainfed crop management, especially wrong tillage and crop residue management, led to reduce the diversity of soil biological quality, especially soil macrofauna community, in semiarid region. This study was conducted to investigate the effect of 5 year conservation agriculture operation techniques on the quality and the diversity indices of soil macrofauna community in the rainfed lands in the west of Iran. This experiment was carried out in the statistical format of split‐split plots based on a randomized completely block design with three replications. The main treatments include control or conventional tillage, compound tillage, chisel tillage, and direct cultivation (no tillage) with three sub‐treatments of plant residues (no residues, one‐third, and two‐thirds of plant residues) in rainfed wheat (Triticum aestivum) rotation with rainfed chickpea (Cicer arietinum). Changes in soil biological quality indicators, such as soil microbial respiration were measured. Also, the indicators related to the population of soil macrofauna, including biodiversity index, uniformity index, and species richness, were measured and the effect of treatments on the measured indicators were compared with the classical statistical method of analysis of variance and Duncan's mean comparison test. The results showed that conservation agricultural treatments, including no‐tillage treatment, have led to significant increase of 19% and 15% of macrofauna biodiversity index in wheat and chickpea, respectively. Also, keeping one‐third of the wheat residues has led to an 18% increase in the biodiversity index of the soil macrofauna during the evaluation period. Biodiversity index and taxonomic richness of soil macrofauna were generally higher in the years of wheat than chickpea, and on the contrary, the species uniformity index of soil macrofauna biological community was higher in chickpea than wheat. Core Ideas Conservation tillage increased 20% of macrofauna biodiversity compared to conventional tillage. Keeping one‐third of crop residues increase soil macrofauna biodiversity about 18% comparing conventional method. Biodiversity and taxonomic richness of macrofauna were higher in wheat than in chickpea fields. The soil macrofauna species uniformity was higher in chickpea than in wheat fields.

Elliptical vibration chiseling is proposed based on a game-changing process principle for the high-efficient texturing of ultrahigh-aspect-ratio surface microstructures. Uniformed microstructures with an aspect ratio of 2–12 in the spacing scale of 1–10 μ m have been successfully fabricated using elliptical vibration chiseling. The developed process model of elliptical vibration chiseling has been verified by the measured results of the microstructures’ geometric parameters. An inclined elliptical trajectory of tool vibration is more suitable for elliptical vibration chiseling than the standard elliptical trajectory. The deterministic process effects on the surface generation of microstructure in elliptical vibration chiseling have been demonstrated. High-aspect-ratio metallic surface microstructures are increasingly demanded in breakthrough applications, such as high-performance heat transfer enhancement and surface plasmon devices. However, the fast and cost-effective fabrication of high-aspect-ratio microstructures on metallic surfaces remains challenging for existing techniques. This study proposes a novel cutting-based process, namely elliptical vibration chiseling (EV-chiseling), for the high-efficiency texturing of surface microstructures with an ultrahigh aspect ratio. Unlike conventional cutting, EV-chiseling superimposes a microscale EV on a backward-moving tool. The tool chisels into the material in each vibration cycle to generate an upright chip with a high aspect ratio through material deformation. Thanks to the tool’s backward movement, the chip is left on the material surface to form a microstructure rather than falling off. Since one microstructure is generated in one vibration cycle, the process can be highly efficient using ultrafast (>1 kHz) tool vibration. A finite element analysis model is established to explore the process mechanics of EV-chiseling. Next, a mechanistic model of the microstructured surface generation is developed to describe the microstructures’ aspect ratio dependency on the process parameters. Then, surface texturing tests are performed on copper to verify the efficacy of EV-chiseling. Uniformed micro ribs with a spacing of 1–10 μ m and an aspect ratio of 2–5 have been successfully textured on copper. Compared with the conventional EV-cutting that uses a forward-moving tool, EV-chiseling can improve the aspect ratio of textured microstructure by up to 40 times. The experimental results also verify the accuracy of the developed surface generation model of microstructures. Finally,the effects of elliptical trajectory, depth of cut, tool shape, and tool edge radius on the surface generation of micro ribs have been discussed.

Core Ideas Compared corn–soybean rotations with cover crops vs fallows under no‐till or till. Corn–soybean rotations with cereal rye after corn decreased soil NO3–N by 42%. Soil attributes and crop yields were generally unaffected by cover crops use. Tillage increased soil organic matter and exchangeable K compared to no‐till. Tillage reduced soybean yields by 245 kg/ha compared to no‐till. Cover crops (CCs) have been heralded for their potential to improve soil properties, retain nutrients in the field, and subsequent crop yields, yet support for these claims within Illinois remains limited. Cover crops were used in corn (Zea mays L.)–soybean [Glycine max (L.) Merr.] rotations. We assessed five sets of CCs vs. fallow controls under no‐till (NT) and chisel till (Till) on soil attributes and crop yields, encompassing one complete rotation cycle. The experimental layout was a split split‐block where whole plot treatments (P, rotation phase; and Y, year) had a Latin square design and subplot treatments of tillage (NT vs. Till) were split into sub‐subplot treatments of CC rotations. We measured soil properties, crop yields, CC stand counts in late fall, and spring biomass samples, each year. Tillage increased the level of soil organic matter (SOM) and exchangeable potassium (K) within our systems yet significantly decreased the yield of soybean by 245 kg/ha. Compared to winter fallow, soil attributes under corn–soybean rotations that included CCs did not show any statistically significant change after one cycle of production except increased N scavenging with cereal rye growing after corn harvest. Inclusion of CCs in the corn–soybean rotation did not affect cash crop yields in either till or NT systems. Our results show that cereal rye is the CC with the best potential as an N scavenger in the corn–soybean rotation, but claims of crop yield increases in the short term are not supported.

Different soil management systems can change the sugarcane yield and quality parameters for sugar/ethanol production. The objective of this study was to evaluate the effects of subsoiling on the inter-row of sugarcane ratoons after the second harvest on productivity and technological quality. Productivity was estimated in tonnes of sugarcane per hectare (TSH), and technological quality parameters were apparent sucrose percentage (Pol) and total sugar recoverable per hectare (TRS). The apparent sucrose percentage and total recoverable sugar were measured in tonnes per hectare, corresponding to the parameters TSH and total recoverable sugar in tonnes per hectare (TTRSH), respectively. This research was carried out at the Experimental Sugarcane Station at the Federal Rural University of Pernambuco in the northeast region of Brazil. A randomized complete block design was used, with two treatments: conventional tillage and inter-row subsoiling. Subsoiling provided a significant gain of stalk yield of 5.53 tonnes per hectare. The other parameters evaluated did not differ significantly.

Gear drives are widely used in various fields and applications due to their properties and capacity. Their versatility, durability, and ability to transmit high torques as well as precision and reliability make them extremely useful in many fields of technology. They are widely used in industrial and energy machinery, vehicle drive systems, aerospace, medical devices, and many other areas. Gears can be manufactured using many technologies. This work focuses mainly on machining with particular emphasis on high-performance new technologies. The process of mathematical modeling of the gear and the machined profile is strongly related to CNC machining technologies. A robust correlation of systems supporting the design and modeling of sliding gears needed for the manufacturing process is presented in the article. It is very important to properly assess gears with correct manufacturing in accordance with a specific standard. The article presents an analysis of available methods for controlling gears using coordinate measurement techniques. Gear machining methods were assessed in terms of the technologies used as well as their productivity and manufacturing tolerance.

Cover crops (CCs) are considered one of the few agronomic strategies to help reduce environmental pollution, while improving soil properties. However, the use of tillage could negate those benefits entirely. Therefore, the goal of this study was to monitor soil properties and cash crop yields from five different CC rotations compared to fallow controls throughout Illinois. A split‐block arrangement of tillage (chisel tillage vs. no‐till) and CC rotations (six levels) in a randomized complete block design with four replications was set within each phase of the corn (Zea mays L.)–soybean [Glycine max (L.) Merr.] rotation at six locations, spanning 2–5 yr. Spring biomass was greatest in the CC rotations with cereal rye (Secale cereale L.), hairy vetch (Vicia villosa Roth), and annual ryegrass (Lolium multiflorum Lam.) due to the four times greater survival percentage. Rotations with annual ryegrass reduced soil nitrate compared to bare fallows. Yet, the freshly added CC biomass only produced minimal increases in soil organic matter (SOM) compared to the other CC species. This rotation also reduces corn yields as is commonly observed when growing a grass CC species before a grass cash crop (corn). Chisel tillage was found to increase corn yields and reduce soil P levels compared to no‐tilled plots regardless of CC rotation. In contrast, soybean yields were not affected by CCs or tillage options. With few choices of CCs that can overwinter in Illinois, our study provides necessary information to evaluate CC management practices and re‐evaluate our current strategies.

Cube corner microstructure is a typical shape of retroreflective micro-structured surface, which has been widely applied in different advanced fields. With the cube corner size down to micrometers, the machining difficulty and cost increase significantly. Diamond micro chiseling (DMC) process has been proposed and proved to be an effective method for machining the cube corner microstructure. However, some challenges still exist during the DMC process, such as time-consuming, tool wear and machining defects. In this paper, a further study of the modified DMC method is reported to eliminate the machining defects and increase the processing quality. Although the previous DMC method could eliminate the cutting traces and burrs of microstructure and reduce the processing time considerably, the slight overcut was still found at the corner between two adjacent facets of the cube under a more precise observation. Therefore, to solve the overcut of the machined microstructure and improve the machining quality, the reason for the overcut is analyzed in-depth, and subsequently, the solution is proposed. The experiment results indicate that the optimization of tool path is more effective than the cutting velocity optimization. By using the optimized tool path, the machining parameters are further adjusted, and a better surface roughness result is acquired on the machined cube facets.

Reducing soil disturbance may limit erosion, but many still consider tillage essential for seedbed preparation, particularly on poorly drained soils. Our objective was to quantify tillage and fertilizer management effects after 45 yr 21 in continuous corn [Zea mays L.] [CC] and 24 in corn–soybean [Glycine max (L.) Merr.] [CS] rotation on a somewhat poorly drained silt loam near Belleville, IL. Four tillage (moldboard plow [MP], chisel tillage [ChT], alternate tillage [AT], and no‐till [NT]) and five fertilizer (no fertilization, N‐only, N+NPK starter, NPK+NPK starter, and NPK broadcast) treatments were evaluated. With N, P, and K fertilizer, yields were similar for tilled and NT treatments, averaging 8.73 Mg ha−1 for CC and 11.93 Mg ha−1 and 3.70 Mg ha−1 for rotated corn and soybean. Below recommended soil‐test values resulted in NT yielding less than tilled treatments even though soil test P, K, and pH were similar. No‐till with N, P, and K increased soil organic matter (OM) to 27.6 g kg−1 (20.5 g kg−1 in all other treatments), with the greatest increase from 0‐ to 5‐cm. No‐till treatments showed stratification of P and K, but it had no effect on yield. No excessive pH stratification was observed. Overall, fertilizer management predominantly influenced crop yield and with complete NPK management non‐tilled yields were similar to tilled, even on flat, somewhat‐poorly drained soils. No‐till with NPK management therefore may allow farmers to maintain high yields while reducing soil and nutrient losses.

Prefabricated Ultra-High-Performance Concrete (UHPC) and cast-in-place Normal Concrete (NC) composite members are increasingly used in bridge engineering because they combine high performance with cost-effectiveness. The bond at the UHPC-NC interface is critical as it directly impacts the composite structure’s safety. This study employed 3D laser scanning acquired the UHPC substrate geometry, utilized fractal dimension analysis to quantify the interface roughness, and adopted the slant shear test to evaluate the effects of retarder application mass and hydration delay duration on roughness and bond strength. The research results indicate that the failure modes of UHPC-NC specimens can be categorized into interface shear failure and NC splitting tensile failure. With the extension of hydration delay duration, both the interface roughness and bond strength show a decreasing trend. The influence of retarder dosage on interface roughness and bond strength exhibits a threshold effect. This study also confirms the effectiveness of fractal dimension as a quantitative tool for characterizing the macroscopic roughness features of the bonding interface. The findings of this paper provide a solid theoretical basis and quantitative support for optimizing key process parameters such as retarder dosage and precisely controlling hydration delay duration, offering significant engineering guidance for enhancing the interface bonding performance of UHPC-NC composite structures.

Subsoil tillage loosens compacted soil for better plant growth, but promotes water loss, which is a concern in areas that are commonly irrigated. Therefore, our objective was to determine the physiological responses of high yield spring maize (Zea mays L.) to subsoil tillage depth when grown in the Western plain irrigation area of Inner Mongolia, China. Our experiment during 2014 and 2015 used Zhengdan958 (Hybrid of Zheng58 × Chang7-2, produced by Henan academy of agricultural sciences of China, with the characteristics of tight plant type and high yield) and Xianyu335 (Hybrid of PH6WC × PH4CV, produced by Pioneer Corp of USA, with the characteristic of high yield and suitable of machine-harvesting) with three differing subsoil tillage depths (30, 40, or 50 cm) as the trial factor and shallow rotary tillage as a control. The results indicated that subsoil tillage increased shoot dry matter accumulation, leading to a greater shoot/root ratio. Subsoil tillage helped retain a greater leaf area index in each growth stage, increased the leaf area duration, net assimilation rate, and relative growth rate, and effectively delayed the aging of the blade. On average, compared with shallow rotary, the grain yields and water use efficiency increased by 0.7–8.9% and 1.93–18.49% in subsoil tillage treatment, respectively, resulting in the net income being increased by 2.24% to 6.97%. Additionally, the grain yield, water use efficiency, and net income were the highest under the treatment of a subsoil tillage depth of 50 cm. The results provided a theoretical basis for determining the suitable chiseling depth for high-yielding spring corn in the Western irrigation plains of Inner Mongolia.