Experimental Study of Cassava Sun Drying

ABSTRACT

Sun drying experiments were performed to compare drying of cassava chips in sheet-metal trays with drying on mesh wire trays: In the sheet-metal trays, there was air flow across the top of the bed chips, while the mesh wire trays permitted air to flow through the bed. Drying rate was faster and more uniform in the trays with through-flow air circulation. Higher temperatures were reached by chips in the sheet-metal trays than those in the mesh wire trays because of contact heating, but the drying rate was lower because of the reduced air flow.     

Detecting vegetable oil adulteration in hazelnut paste (Corylus avellana L.)

The possibilities of detecting hazelnut paste adulterated with refined and non-refined vegetable oils have been studied. Research was focussed mainly on peanut, high oleic-acid sunflower, corn and soybean oils which have a similar composition to hazelnut oil. The analytical procedures to detect fatty acid (FA), triacylglycerol (TAG) and tocopherol profiles as indicators of adulteration were determined. The better indicators experimentally determined were seven FA (palmitic, stearic, linoleic, linolenic, arachidonic, behenic and lignoceric acids) and different TAG with three unsaturated FA (the code letters used for FA are: P = C_16:0; S = C_18:0; O = C_18:1; L = C_18:2;; L_n = C_18:3) (LLL_n, LLL and OOO), two unsaturated FA (POL, PLL and SOO), and one unsaturated FA (PPL). As expected, when refined vegetable oils were added to hazelnut paste, the increment of stigmasta-3,5-diene allowed detection at levels of 2% oil added. Limits of detection were measured using standard and adulterated hazelnut with different amounts of non-refined vegetable oils added (5%, 10%, 20% and 30%). The distribution of tocopherols and tocotrienols is highly useful, except in the case of added sunflower oil. The differences between the experimental and theoretical values of the TAG with equivalent carbon number (ΔECN) of 42 does not improve the detection limit of hazelnut paste adulterated with peanut or sunflower oils. Similarly, tocopherols usually added to refined vegetable oils as an antioxidant were also determined.     

植物油酸值、过氧化值的测定方法研究

为解决国标法测定植物油酸值、过氧化值溶剂安全性问题，以核桃油为实验材料，建立以更安全且容易获取的石油醚、二氯甲烷分别代替GB 5009.229—2016和GB 5009.227—2016中乙醚、三氯甲烷，测定植物油的酸值和过氧化值的方法，考察方法的精密度,采用国标法和所建立方法测定4种植物油的酸值、过氧化值，并对结果进行t检验，考察方法的准确度。结果表明：所建立方法平行测定了6次核桃油的酸值、过氧化值，其相对标准偏差（RSD）分别为2.055%、1.318%；国标法和本实验方法同时测定4种植物油的酸值、过氧化值p值均大于0.05，两种方法不存在显著性差异。所建立的方法精密度和准确度均较好，并且提高了检测安全性，可用于植物油的酸值和过氧化值测定。     

Effect of Tissue Infrastructure on Electric Conductance of Vegetable Stems

ABSTRACT: This study measures the electric conductance and examines the microscopic structure of bamboo shoots, sugarcane, lettuce stem, and mustard stem. The electric conductance readings vary from 0.09 S/m to 0.72 S/m across the stem, and from 0.19 S/m to 0.46 S/m along the stem. The electric conductance along the stem is higher than the electric conductance across the stem in bamboo shoots and sugarcane, while the reverse is true in lettuce stem and mustard stem. The orientation of vascular bundles and the shape of parenchyma cells are proposed to account for the different conductance readings from the same vegetable in different directions. The orientation of vascular bundles appear to influence electric conductance more than the shape of parenchyma cells when both factors are present in the same time.     

Durability testing modified compression ignition engines fueled with straight plant oil

Many short-run studies point to the potential for direct fueling of compression ignition engines with plant oil fuels. There is a much smaller body of work that examines the potential for these fuels in long-run tests that illuminate engine endurance and longevity issues. Generally, longevity studies involving direct fueling of engines with straight plant oils have shown significant impact to the life of the engine, though test results vary widely depending on the oil, engine type, test conditions, and measurement approach. This study utilizes a previously designed modification kit [1] to investigate the longevity implications of directly fueling straight plant oil in an indirect injection (IDI) listeroid type, slow speed stationary engine common in agro-processing applications in developing countries. Specifically this study focuses on the lubrication oil by developing a model to characterize the engine wear and estimate lube oil change frequency. The model is extended to an analysis of the piston rings. Cylinder liner wear, emissions, engine performance, and a visual investigation of several critical engine components are also studied.     

植物单宁—蛋白质相互作用的计算机模拟

研究植物单宁-蛋白质的相互作用在制革、医药等方面具有很重要的意义，而计算机模拟技术理论在相关的研究中得到广泛的应用。本文综述了单宁-蛋白质反应的机理和分子模拟及理论计算中常用的方法，并展望了其应用前景。     

Alternate oils in fish feeds

Nearly half of the fish consumed as food worldwide are raised on fish farms rather than caught in the wild, as shown by FAO statistics. The increasing aquaculture of predatory carnivorous fish demands new sources of feed constituents, particularly oils at the moment. Common terrestrial plant oils contain only traces of the long‐chain polyunsaturated fatty acids. In connection with fish feed, especially the lack of n‐3 “marine fatty acids” is obvious. Recommendations on the required amounts of the fatty acids DHA (22:6n‐3) and EPA (20:5n‐3) exist from 1994. When plant oil‐based diets are fed during the growing phase and replaced by a fish oil‐based diet during a period prior to slaughter, most of the beneficial lipid composition of fish in terms of human dietary recommendations is restored. Little attention has been focused on the fish welfare in connection to substitution of dietary oil sources, and studies are still scarce. New fish diets will rely heavily on the use of alternate ingredients such as plant oils also for carnivorous cold‐temperate water fish species. In the future, an addition of synthetic or GMO‐produced “marine” fatty acids is a possible scenario. The aim of this review is to highlight some plant oils used in fish feeds, with special emphasis on compounds other than fatty acids. We also include some results from an ongoing study, where the effect of dietary soy oil on gonad maturation in Atlantic cod (Gadus morhua) is indicated.     

果蔬采摘欠驱动灵巧机械手的设计

欠驱动机构是指驱动器数目少于机构本身自由度数目的机构。为了实现果蔬的无损采摘,通过理论分析、指端结构设计、传动机构设计和驱动机构设计与建模仿真,设计出一种灵活性高、结构简单的果蔬采摘欠驱动灵巧机械手。该机械手抓取物体时具有形状自适应能力,可完全包络物体实现无损采摘,且体积小、成本低,能够适应农业采摘自动化技术的推广。     

基于植物油和矿物油的10 kV油浸变压器外部热源耐火实验

为了探究不同油浸变压器受火情况下的火灾动力学过程,搭建了全尺度变压器火灾实验平台,分别针对基于RAPO天然酯植物油和25号变压器油的10 kV油浸变压器开展了外部热源耐火实验。研究结果表明,在同一外部热源条件下,矿物油变压器在受火状态下9 min左右即出现猛烈的喷射火灾现象,喷射出的矿物油品同时导致了大面积的池火和流淌火灾,使得火灾进一步加剧。相比而言,植物油变压器燃烧相对平缓,在24 min左右才出现轻微的喷射火现象,但并未造成明显的火灾加剧,且实验结束后变压器周边残存大量未燃植物油。在燃烧实验中,植物油的温升速率约为0.18 ℃/s,显著低于矿物油的0.24 ℃/s,也进一步说明了植物绝缘油的安全性。从消防安全角度,植物油变压器的火灾安全性远胜于矿物油变压器,具有较好的应用前景。