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Cracked carrots account for a large proportion of defective carrots, which are usually discarded or used as feed, resulting in resource waste and economic benefit loss. Cracked carrots can be used as raw materials for further processed carrot products after being trimmed. So, an auxiliary device was developed combining PLC (Programmable Logic Controller) and machine vision to achieve clamping and crack defect localization for intelligent trimming of crack defect. The carrot was orientated based on the area method, rotated by flexible jaws and a rotating cylinder to make the carrot head and tail aligned. The clamping device could non‐destructively clamp carrot in axial and radial direction with a force threshold of 10 and 22 N respectively, and rotate carrot to make the crack defect upwards. The results showed that the recognition accuracy of carrot head and tail orientation was 98%, the average deviation of carrot centroid clamping position was less than 9 mm at a speed of 300 mm/s, the rotational positioning time was less than 3 s and the number of adjustments were no more than 2 at a motor speed of 180 rpm, which could meet the subsequent trimming requirements. Practical applications: Trimming the cracked area of carrots can reduce bacterial growth and decay, which is beneficial for subsequent processing and reduces resource waste. This article designs a carrot auxiliary trimming device, which uses image processing technology to recognize the orientation of the head and tail of carrots and the cracked area, and uses automated equipment to achieve stable clamping of carrots and make the cracked area face the trimming tool. This study is beneficial for the refined management of agricultural products. [ABSTRACT FROM AUTHOR]

Forked carrots are often used as animal feed or discarded directly, which affects ​the economic returns of growers and leads to resource waste and environmental pollution. After trimming, forked carrots become easier to peel and can be further processed. However, the lack of relevant studies and equipment hinders the full use of forked carrots, and the identification of fork points and determination of the trimming path are the main challenges in trimming forked carrots with unique and diverse shapes. Therefore, an automatic carrot‐trimming path recognition solution based on contour analysis and machine learning was proposed in this study to address the above challenges. Specifically, a cascaded model and a parallel model consisting of Multilayer Perceptron (MLP) and Support Vector Machine (SVM) were constructed to identify fork points, and three trimming path determination methods based on fork points and carrot contours were proposed. The results demonstrated cascaded and parallel models achieved 100% and 92.7% recall rates, respectively, with accuracy rates of 90.4% and 100% and repetition rates of 97.1% and 96.4%. Among the trimming path determination methods, both the dynamic convex hull method and the static convex hull method achieved a convexity of 94.7%, surpassing 93.1% for the slope method. The static convex hull method exhibited the fastest speed in determining the trimming path, taking only 0.0032 s per carat. The parallel model and the static convex hull method could be effectively used for online determination of the trimming path for forked carrots. Practical applications: Trimming forked carrots enhances usability, reduces resource wastage, and mitigates environmental pollution. Leveraging contour‐based machine learning algorithms, we achieved precise fork point recognition with broad applicability. Using fork point and carrot contour data, we determined trimming paths that render carrots convex for mechanical peeling. This approach contributes to advancing sustainable agriculture by optimizing resource utilization. [ABSTRACT FROM AUTHOR]

A CuI/L‐proline‐catalyzed reaction of 2‐(2‐bromophenyl)‐4,5‐diaryl‐1H‐imidazole and potassium ethylxanthate unexpectedly gave bis(2‐(4,5‐diaryl‐1H‐imidazol‐2‐yl)phenyl)sulfane derivatives in high yields, rather than 2,3‐diphenyl‐5H‐benzo[e]imidazo[1,2‐c]thiazine‐5‐thione. This cascade procedure provided an efficient method to synthesize diphenylsulfanes using potassium ethylxanthate as a new type of sulfur source via the Csp2S bond Ullmann reaction twice. [ABSTRACT FROM AUTHOR]

A silver‐catalyzed protocol for [3+1+1] annulation of nitrones and isocyanoacetates is reported. The reaction is proposed to proceed through sequential [3+2] cycloaddition, ring‐opening, cyclization‐oxidation, and dealkylation, allowing access to a broad scope of valuable polysubstituted imidazoles in high yields. [ABSTRACT FROM AUTHOR]

A series of Pd complexes of picoline-functionalized N-heterocyclic carbenes with different substituents were synthesized. The molecular structures of selected complexes were determined by X-ray diffraction studies, showing a pseudo-square-planar structure with a Pd center surrounded by carbene, pyridine, and two chloride ligands. The influence of the different substituents on the structure and reactivity of the complexes has been studied. The catalytic properties of the complexes were investigated in the Mizoroki-Heck reaction for cross-coupling of bromobenzene with a variety of aryl halides. Their performances varied in these reactions but showed good product regioselectivities. [ABSTRACT FROM AUTHOR]

A series of pyridine-functionalised bis(benzoimidazolium) dichlorides, dibromides and dihexafluorophosphate with different alkyl bridged length (n = 2-4) were synthesised in high yield. All the compounds are new and fully characterised by 1H and 13C NMR, IR and elemental analyses. [ABSTRACT FROM AUTHOR]