市售茶饮料中茶多酚含量的调查与分析

本文对21种市售茶饮料分别进行感官评定、茶多酚含量测定,同时考察开盖时间对茶饮料中茶多酚损失率的影响。结果表明,被检21种茶饮料感官方面基本都能体现原茶风味,总体品质良好;各类茶饮料中茶多酚含量差异明显,除2种调味茶饮料外,其它样品茶多酚含量均符合国家标准,其中一款乌龙茶饮料的茶多酚含量高达2097.90 mg/kg,绿茶饮料中茶多酚含量在530.35-936.77 mg/kg之间,普遍高于红茶饮料茶多酚含量136.99-639.92 mg/kg,花茶饮料中茶多酚含量相对较少;开盖后茶多酚损失率随时间的延长而明显增加,且在前40min最为严重。     

抽油机设计计算软件的开发

根据游梁式抽油机和无游梁式抽油机的特点,针对不同类型抽油机的设计,提出了抽油机设计计算软件的编制方法;对工艺计算中的泵挂深度、平衡扭矩、日产液量、电动机功率和悬点载荷等参数的计算进行了推导,编制了程序计算流程框图,并以CYJQ12—4.2—3HB型前置式抽油机为例,给出了该软件的应用方法。最后指出该抽油机设计计算软件可用于机械平衡的所有抽油机设计,包括游梁式抽油机和无游梁式抽油机,在使用过程中,只需对软件中的基本计算、动力计算、运动计算及相应的TF值及PR值计算进行修改即可。     

16型异相游梁复合平衡抽油机性能测试

根据我国油田的开发现状及抽油机的应用情况 ,提出了 16型抽油机改进设计方法 ,并对改进后的CYJY16— 5 4— 89HF B型异相游梁复合平衡抽油机进行了整机性能测试 ,测试结果表明 ,该型抽油机的各项性能指标均符合SY T5 0 4 4— 93《游梁式抽油机》及SY T5 2 12— 97《游梁式抽油机质量分等》标准之要求。现场应用表明 ,该 16型抽油机与常规抽油机相比 ,减速器峰值扭矩下降 4 2 %以上 ,节能 30 %以上 ,并且结构简单、承载能力大、可靠性高。     

土木工程结构健康监测中的压电传感技术研究

从压电方程入手,分析了采用压电陶瓷传感器进行动态应变传感的原理和计算公式。通过实验研究了不同激振频率下压电传感器的动态响应,其电压特性曲线表明该传感器灵敏度高,且输入输出具有较好的线性关系。另外,输出电压与传感元件的厚度有一定关系,灵敏度随着厚度的增大而增大。此项研究结果为结构健康监测工程应用奠定了理论基础。     

CYJ10-3-53HB型常规抽油机改进设计

以CYJ10-3-53HB型常规抽油机为例,论述了抽油机的改进设计过程。对驴头、游梁、横梁、连杆、曲柄平衡装置、底座、支架等部件按照国际上同类产品的通用设计方法进行了具体的改进设计,对改进后的游梁、连杆、横梁进行了校核计算,并运用ANSYS结构分析软件对支架进行了应力和刚度分析。结果表明,常规抽油机经过改进设计之后,不仅结构趋于合理,改善了受力状态,大大降低了制造成本,而且整机质量减轻了7.37%。     

路缘沉积:利用原型思维过程探究如何通过路缘及路肩设计截留暴雨中的路面污染物

The design of a curb is straight forward. The curb itself provides a conveyance of stormwater, facilitating the movement of water and pollutants from the street into waterways. Pollutants such as sediment, nutrients from lawn fertilizers, bacteria, viruses, pesticides, metals, and petroleum byproducts accumulate on the road surface and are released during storm events, carried to storm drains, and deposited into waterways, often without treatment. Once pollutants enter the waterways they impact the ecosystem and affect water quality. How can discrete standards—like a curb—be leveraged to have larger systemic impacts? The redesign of the curb to perform as a magnet for pollutants can challenge this design standard. During the summer of 2019, the interdisciplinary research team tested alternatives to the standard concrete curb and apron at Ohio State University. The team used an iterative design process to add patterning and crenellations to the face of the curb and apron. Using full scale models to test simulated storm events, the team collected data to evaluate the performance of 21 alternative designs. The results suggest the new combined curb and apron designs can abstract pollutants from roadways before they are detrimental to water bodies and aquatic ecosystems.     

潞江坝藿香不同部位营养成分及微量元素含量测定

本文通过对云南省潞江坝藿香茎、叶、花穗的水分、总灰分、粗蛋白质、粗脂肪、还原糖、微量元素含量进行测定,为潞江坝藿香食用安全性提供理论依据,推动发展特色农产品。结果表明,藿香不同部位的营养成分存在显著差异(p 0.05),其中水分含量:叶花穗茎。总灰分含量:叶花穗茎。粗蛋白质含量:花穗叶茎。粗脂肪含量:花穗叶茎。还原糖含量:叶茎花穗。藿香三个部位的微量元素含量丰富。     

Tribological behavior of three typical bearing alloys under influence of additives

The influences of lubricating additives on the tribological behavior of lead, tin, copper base bearing alloys-0.45%C steel rubbing pairs under the condition of boundary lubrication were researched. The results show that because of the difference of physical chemistry performance at bearing alloys and steel, some conventional lubricating additives which is beneficial to steel-steel rubbing pairs is harmful to these bearing alloys-steel rubbing pairs,and the wear volume can be increase by 7 times under the test condition. The measure results of contact resistance during the test process show that the higher the contact resistance at rubbing surface, the better the tribological behavior of tribo-system. Moreover for the lead base and tin base bearing alloys-0.45%C steel rubbed pairs, the thicker the compact oxide layer of steel surface, the larger the friction coefficient and wear volume, which demonstrates that oxidation wear plays an important part in the wear process.     

抽油机变频变压节能控制器的设计

针对目前我国抽油机节能研究的现状，提出了抽油机变频变压节能控制器的设计方案，给出了该方案的工作原理图和工作流程图，并对抽油机变频变压节能控制器的特点和性能进行了分析，实践表明，该节能控制器不仅性能稳定，操作简单，还可节电27％以上。