The growing demand for agricultural output and limited resources encourage precision applications to generate higher-order output by utilizing minimal inputs of seed, fertilizer, land, and water. An ...electronically operated planter was developed, considering problems like ground-wheel skidding, field vibration, and the lack of ease in field adjustments of ground-wheel-driven seed-metering plates. The seed-metering plate of each unit of the developed planter is individually driven by a brushless direct current (BLDC) motor, and a BLDC motor-based aspirator is attached for pneumatic suction of seeds. The revolutions per minute (RPM) of the seed-metering plate are controlled by a microcontroller as per the received data relating to RPM from the ground wheel and the current RPM of the seed-metering plate. A feedback loop with proportional integral derivative (PID) control is responsible for reducing the error. Additionally, each row unit is attached to a parallelogram-based depth control system that can provide depth between 0 and 100 mm. The suction pressure in each unit is regulated as per seed type using the RPM control knob of an individual BLDC motor-based aspirator. The row-to-row spacing can be changed from 350 mm to any desired spacing. The cotton variety selected for the study was RCH 659, and the crucial parameters like orifice size, vacuum pressure, and forward speed were optimized in the laboratory with the adoption of a central composite rotatable design. An orifice diameter of 2.947 mm with vacuum pressure of 3.961 kPa and forward speed of 4.261 km/h was found optimal. A quality feed index of 93% with a precision index of 8.01% was observed from laboratory tests under optimized conditions. Quality feed index and precision index values of 88.8 and 12.75%, respectively, were obtained from field tests under optimized conditions.
A pneumatic spray delivery (PSD)-based solid set canopy delivery system (SSCDS) consists of in-line reservoirs and micro-emitter assemblies distributed throughout perennial crop canopies. The ...existing PSD-based SSCDS uses a large number of reservoirs, i.e., one unit per 3 m of linear spacing, which resulted in high installation and maintenance costs. These reservoirs also produces up to 25% post-spray chemical losses. Therefore, this study aimed to optimize the volumetric capacity and functionality of the existing reservoir for an efficient spray performance and the large-scale commercial adaptation of PSD-based SSCDS. Three reservoirs with volumetric capacities of 370 (1×), 740 (2×), and 1110 mL (3×) were developed to cover a spray span of 3.0, 6.1, and 9.1 m, respectively. Five system configurations with modified reservoirs and spray outlets were evaluated in the laboratory for pressure drop and spray uniformity. The three best system configurations were then field evaluated in a high-density apple orchard. These configurations had reservoirs with 1×, 2×, and 3× volumetric capacity and micro-emitters installed in a three-tier arrangement. Each replicate configuration was installed as a 77 m loop length encompassing 50 apple trees trained in a tall spindle architecture. A pair of water-sensitive paper (WSPs) samplers (25.4 × 25.4 mm) were placed on the abaxial and adaxial leaf surfaces in the bottom, middle, and top third of the canopy to evaluate the spray coverage (%). The PSD-based SSCDS showed no significant difference at the 5% level in terms of coverage among the three reservoir treatments. Coverage was more evenly distributed among the top, middle, and bottom zones for the 2× and 3× as compared to the 1× reservoir treatment. Overall, compared to the 1× reservoirs, the 2× and 3× reservoirs could potentially reduce the system costs by USD 20,000 and USD 23,410 ha−1, respectively, for tall spindle apple orchards and potentially reduce maintenance needs as well.
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•The droplet characteristics of UAV based spraying system were evaluated.•ImageJ produced most consistent droplet characteristics among tested methods.•RSM techniques optimized the ...operating parameters of UAV-based spraying system.•GWO-ANN was the best neural networks architecture to predict droplet deposition.
Modern agriculture relies on pesticides to increase crop yields, but these chemicals are also hazardous. Although conventional sprayers were designed for effective pest management, they nonetheless pollute the environment and endanger operators' health. Unmanned aerial vehicle (UAV)-based sprayers overcome the aforesaid problem and can precisely target the areas that need treatment and difficult to reach for human operators. This study evaluated a UAV-based spraying system in a cotton field, employing imaging techniques such as Laser Droplet Analyzer, Deposit Scan, ImageJ, and Drop leaf. Furthermore, the system was optimized using response surface methodology, and deposition predictive analysis was conducted using a hybrid GWO-ANN approach. The volume median diameter, number median diameter, relative span, and uniformity coefficient were in the range of 95–248 µm, 65–174 µm, 0.8–1.7 %, and 1.3–1.7 %, respectively. Optimizing the working speed (3.3 m/s), working height (1.0 m), and discharge rate (2.0 L/min) resulted in a droplet density of 50.3 droplets/cm2, deposition of 0.20 µL/cm2, and coverage of 9.27 %. The GWO-ANN prediction model yielded R2, RMSE, and MAE values of 0.878, 0.01729, and 0.01368, respectively. Optimizing operational parameters through multiple measurement techniques enhance flexibility and effectiveness of UAV-based spraying system, facilitating wider deployment in remote agricultural areas for agrochemical applications.
The study was conducted during November, 2021 at Department of FMPE, CAET, OUAT, Bhubaneswar, Odisha, India to investigate the torque requirement and ascertain optimum peripheral cutting velocity of ...rotary cutting disc based on varying stem diameter and moisture content of green gram . The cutting operation was simulated to find the cutting torque in the instrumented soil bin, which comprises of test trolley, processing trolley and vertical rotor assembly with vertical shaft having serrated cutting disc. Sample plant stems of green gram were firmly fixed in the plant stem holder, and buried beneath the soil to simulate the natural standing of the crop as in the actual field condition. The cutting torque required to cut the stem of green gram at different crop moisture content (39.2, 41.4 and 42.9% (wb)), peripheral cutting velocity (20, 25, 30, and 35 ms-1) and plant stem diameter (2.95, 3.97 and 4.96 mm) was measured. It has been observed that peripheral cutting velocity of disc, stem diameter and moisture content of plant affected cutting torque at 1% level of significance. The cutting torque increased with decrease in moisture content and increase in diameter of plant stem of green gram. The cutting torque increased with an increase in peripheral cutting velocity up to the critical velocity of 30 ms-1, but the value decreased after critical peripheral velocity.
Alkyl Thioglycolates of Aluminium, Titanium and Zirconium Bhatia, Duru; Bhandari, Akshya M.; Kapoor, Ramesh N. ...
Synthesis and reactivity in inorganic and metal-organic chemistry,
19/1/1/, Letnik:
9, Številka:
2
Journal Article
Alkyl thioglycolates of the type Al(OR)G (R = Pr
i
, Bu
t
); M(OR)
2
G (M = Ti, Zr; R = Pr
i
, Bu
t
); MG
2
(M = Ti, Zr), Al
2
G
3
and Al(GH)G where GH
2
is methyl or ethyl thioglycolate have been ...prepared. The isopropoxy derivatives were obtained by carrying out the reaction between the isopropoxide of the corresponding metal with methyl or ethyl thioglycolate in anhydrous benzene in different molar ratios, whereas the tertiary butoxy derivatives were prepared from the respective isopropoxy derivatives by alcohol interchange technique. Molecular weights of soluble titanium and zirconium derivatives show them to be dimeric in nature. Structures have been suggested on the basis of infrared spectral and molecular weight studies.
