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关键词： carotenoid cleavage dioxygenase1 (ccd1)   Gene expression   Intron   Long non-coding RNA   Maize  

摘要： BackgroundBiofortified maize with enhanced carotenoid content was developed to combat vitamin A deficiency. However, it was observed that during storage, carotenoids present in maize grain get degraded and it has been reported that carotenoid cleavage dioxygenase1 (ccd1) is responsible for this *** and resultsIn our current study, comprehensive in-silico analysis deciphered a complete overview of the ccd1 gene in maize including the gene structures, phylogeny, chromosomal locations, promoter analysis, conserved motifs and interacting protein partners. In addition to these, a comparative in-silico analysis of the ccd1 gene in maize, rice and Arabidopsis was performed. An intronic region of ccd1, unique to the maize genome, was matched significantly with a lot of long non-coding RNA and was identified. Also, growth stage-specific ccd1 expression analysis was performed in two maize inbred lines, V335PV and HKI161PV. The results indicate that both inbred lines displayed higher ccd1 expression during reproductive stages compared to vegetative stages, with the highest expression level observed at the milking stage in both *** detailed in-silico characterisation and expression analysis of the ccd1 gene contributes to our understanding of its activity and expression pattern in maize in stage and tissue-specific manner. This study will further provide an effective strategy for manipulating the ccd1 gene to enhance the carotenoid content of maize grain, thereby aiding in the combat against vitamin A deficiency.

关键词： Biochar   Biofuel   Catalytic upgrading   Diesel   Gasoline   Microalgae  

摘要： Developing alternative or new energy sources is essential due to fossil fuel depletion and environmental impacts. Previous studies have synthesized an Ni-functionalized and pyrolyzed rice husk for catalytic refining of oil from microalgae (Scedemus obliquus) and have further optimized the liquid hydrocarbon production. This work further investigated the interacting effects of the operating parameters on gasoline (Y-1) and diesel (Y-2) relative content. The parameters were temperature (A), dodecane-to-oil ratio (B), and pressure (C). The response surface methodology by central-composite design (RSM-CCD) demonstrated that the temperature was the only parameter significantly affecting the relative content of the two fuel products. The previously RSM-CCD optimized condition (A = 246.9 degrees C, B = 3.72, and H-2 pressure = 3.84 MPa), generating the liquid hydrocarbon, produced Y-1 = 77.1 % and Y-2 = 22.9 % with a standard error of +/- 0.7 % and <2.0 % discrepancy from the predicted values. Finally, the specific constituents were further identified as undecane, tridecane, pentadecane, and octadecane for diesel-range products, while octene, octane, nonane, and decane for gasoline-range products. Overall, the study demonstrates the responses of two fuel products under the optimized operating liquid hydrocarbon and further supports the catalytic upgrade considering the identified fuel products.

关键词： 易爆气体   智能检测   Arduino   蓝牙   传感器   物联网  

摘要： 针对现代工厂和实验室中产生的气体,如果无人监控或者监管缺失,可能会导致爆炸等严重后果。如何检测易爆气体已成为智慧物联网技术应用的一个重要方向。为此,设计了一款以Arduino为主控板的易爆气体智能检测系统。系统集成了MQ-7等各类传感器,通过HC-05蓝牙传输模块将各传感器的检测数据传至手机蓝牙客户端。测试结果证明:该系统能够准确检测易爆气体体积分数的变化,一旦数据超过阈值,系统就会启动蜂鸣器报警,并驱动与舵机连接的风扇进行气体消散作业,从而满足自动化监管的需求。

关键词： 无人农机   障碍物检测   RTK-GNSS   激光雷达   欧式聚类  

摘要： 设计了基于RTK-GNSS、VLP-16激光雷达和姿态传感器的障碍物检测与定位系统,具有田间障碍物检测、插秧机位姿获取等功能。系统以久保田2ZGQ-6D(NSPU-68CMD)型号插秧机为实验载体,硬件上由车体位姿采集模块、点云数据采集模块和系统供电模块组成,软件上由坐标转换模块和障碍物检测模块组成。其中,车体位姿采集模块可获取插秧机作业田块的经纬度坐标和车体姿态信息;坐标转换模块可根据车体姿态和经纬度坐标选定插秧机的作业区域,建立插秧机的作业田块坐标系;点云数据采集模块可获取插秧机作业环境的点云信息;障碍物检测模块可根据环境点云信息,通过直通滤波、高斯滤波、地面点云分割、欧式聚类、OBB包围盒拟合和障碍物状态估计计算障碍物的定位坐标,判别障碍物的运动状态;系统供电模块实现障碍物检测系统的稳定供电。在农田环境进行障碍物检测试验,结果表明:系统对障碍物的定位略有波动,障碍物横向移动时,最小偏差为3.0 cm,最大偏差为14.3 cm,平均偏差为6.8 cm;纵向移动最小偏差为1.5 cm,最大偏差为16.0 cm,平均偏差为7.9 cm;在设定的障碍物检测区域内,对静态障碍物和动态障碍物的检测准确率可达到90%。系统能够对田间障碍物进行有效识别和准确定位,但无法对障碍物的类别进行判断。

关键词： 客车   超载检测   烟雾传感器   温度传感器  

摘要： 客车安全事故频发,急需提高客车的智能化水平。以STC89C52单片机为核心,运用多传感器融合技术,设计了客车安全检测系统,对乘车环境进行实时监测。采用红外检测电路统计车内人数,DS18B20温度传感器测量温度,MQ-2烟雾传感器检测可燃性气体浓度,单片机读取测量数据,与按键模块设置的核载人数、温度阈值进行比较,当检测到的数据超过阈值时进行声光报警,同时在LCD上实时显示温度、人数、警报信息等。当客车超载时,与客车的启动系统产生联动,实现超载自动停车。实验表明,该系统能有效抑制客车超载现象,及时提示火灾警情,为市民的安全出行提供保障。

关键词： 电火花小孔加工   频域自编码器   穿透检测  

摘要： 提出了一种基于频域自编码器的电火花小孔加工穿透检测方法,通过对影响穿透检测的加工参数进行特征分析,提取出主要特征;构建了穿透检测训练模型,通过比较自编码器处理后的频域信号和原始频域信号之间的差异判断电极是否穿透工件,得到模型在迭代次数30次时收敛,训练集准确度为99%,验证集精度约为97.1%。验证结果表明:该方法可对电火花小孔加工穿透瞬间进行可靠准确识别。

关键词： CCD   Co-pyrolysis   Expanded polystyrene   Oil palm frond   PAH   Pyrolysis oil  

摘要： The transformation of plastic and biomass waste into fuel promotes sustainable energy alternatives and efficient waste management. In this study, liquid fuel production from co-pyrolysis of oil palm fronds (PF) and expanded polystyrene (EPS) was experimentally investigated in a fixed-bed reactor. The effect of process temperature (T, 300–500 °C), and PF-to-EPS ratio (R, 0.1 to 9) on pyrolysis oil yield (Y_PO) and PAH's composition (PAH_C) was studied using Response Surface Methodology (RSM) based on Central Composite Design (CCD). PF-to-EPS ratio (R) was found to be the most significant process parameter for determining the Y_PO, while T was the most influential process parameter affecting PAH_C. The maximum pyrolysis oil yield of 80.11 wt% and minimum PAH composition of 20.63 % area was obtained at an optimum T of 395 °C and 0.1 R. The pyrolysis oil also contained benzene with a concentration below the established standards. The pyrolysis oil produced under optimum conditions had a calorific value of 41.56 MJ/kg, kinematic viscosity at 40 °C of 0.85 mm²/s, density at 15 °C of 0.93 g/cm³, water content of 0.24 wt%, acidity of 3.46 mg KOH/g, and a flash point of 26.05 °C. Pyrolysis oil can potentially improve gasoline's octane rating because of its high aromatic compound content. © 2024 The Authors

关键词： 深度学习   YOLOv5算法   目标检测   模型训练   图像处理   系统测试  

摘要： 非机动车驾乘人员正确佩戴头盔可以减轻交通意外中的人身伤害,为了检测非机动车驾乘人员头盔状态,基于YOLOv5设计了一款非机动车驾乘人员头盔检测系统。首先通过网络爬虫下载交通监控图像建立数据集,标注图像中的非机动车驾乘人员头盔佩戴状态,分为正确佩戴和未佩戴两种;接着将数据集划分为训练集、验证集和测试集;设置算法的超参数,训练头盔检测模型,开发非机动车驾乘人员头盔检测系统。系统分为用户管理、图像采集、头盔检测、结果分析与显示4个模块,分别实现用户身份验证,交通视频图像获取,利用训练好的模型检测头盔状态,显示头盔检测结果等功能。实验表明,该系统能有效检测非机动车驾乘人员的头盔状态,为道路交通安全提供支持。

关键词： Response surface methodology   Tetracycline   Adsorption   Hexavalent chromium   Adsorption models   Nanoparticles  

摘要： Pollution of water resources by a range of organic and inorganic non-degradable contaminants is becoming increasingly problematic. This study presents a novel Fe3O4/SiO2/ZIF-67 (FSZ) nanocomposite for removing tetracycline (TC) and hexavalent chromium (Cr6+). The synthesis began with the preparation of Fe3O4, SiO2, and ZIF-67 components. Following this, various loadings of the binary SiO2/ZIF-67 were prepared. Finally, the ternary FSZ adsorbents were synthesized by impregnating 1, 3, 5, 7, and 9 wt% of Fe3O4 nanoparticles (NPs) onto the optimized binary SiO2/ZIF-67 NPs. Characterization techniques such as SEM, TEM, BET, EDS, XRD, and XPS were performed. The removal efficiencies were optimized using the RSM-CCD, considering factors like composite dosage, reaction time, pH levels, and contaminants concentration. Optimal composite dosages of 0.69 g/L for TC and 1.68 g/L for Cr6+, pH values of 6.05 for TC and 6.06 for Cr6+, reaction times of 90 min for TC and 57 min for Cr6+, and contaminant concentrations of 25.47 mg/L for TC and 2683.2 ppb for Cr6+ were achieved. Removal rates of 98.53 % for TC and 97.45 % for Cr6+ were achieved under optimal conditions. Moreover, various kinetic and isothermal adsorption models were applied. The FSZ composite maintained high removal efficiencies for Cr6+ (81.14 %) and TC (79.82 %) after four cycles. Its performance was assessed in various water types, including deionized water, river water, and municipal wastewater. Additionally, the FSZ composite effectively removed other contaminants, achieving high efficiencies for cadmium (95.18 %), lithium (83.42 %), arsenic (88.29 %), sulfamethoxazole (87.38 %), doxycycline (96.15 %), and cefixime (81.97 %). Finally, the mechanisms responsible for the removal of TC and Cr6+ were evaluated. The sustainable synthesis of FSZ provides a valuable foundation for future studies focused on Cr6+ and TC removal, offering a potential solution to pressing environmental challenges.

关键词： 检测系统   特征识别   图像处理   稻粒  

摘要： 通过视觉识别图像处理技术对稻谷谷粒进行处理,利用OTSU自适应阈值对稻谷图像进行二值化处理,采用中值滤波对图像进行降噪处理、图像分割和连通区域标记,基于几何形状特征阈值检测算法识别不同种类稻谷的长度、宽度、周长和面积像素值,提出一种综合的阈值通用旋转法,可实现不同谷粒的分类。根据获取谷粒图像样品和采集谷粒数目特征,基于形态学处理和分水岭变换分割算法对谷粒进行数目识别提取,最后根据检测的数目和整碎谷粒特征统计汇总稻谷谷粒的相关参数信息,将谷粒识别结果和相关数据信息保存在数据库中,便于进一步分析。研究结果表明:利用MatLab软件中GUI界面开发的稻谷检测系统对谷粒数目有较好的识别力,精确度达98.327%,对于整碎谷粒的识别误差在可控范围,满足要求与传统人工检测相比,具有检测快速、多样化等优点。