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51.
宋暖  焦阳  李君  陈大川 《电子测试》2020,(10):109-110,90
考试是高校实现人才培养目标的落脚点,探索基于实践项目制作、基于信息化手段、基于非标考题等多元化的过程性考核方式改革,加大过程性考核的分值比重,增加过程性考核方式的趣味性和创新性,优化电类课程考核模式,进而达到全面提升电工电子课程的高阶性、创新性和挑战度的终极目标。  相似文献   
52.
53.
Richard Herriott 《CoDesign》2018,14(3):203-217
This paper examines patient-involvement in the process used to design new hospitals. Denmark is in the midst of a phase of hospital building. This recent experience is studied by means of expert interviews with senior practitioners involved in three projects. Examined thematically, the data covers the structure of the design process, identification and ranking of stakeholders, the methods of user-involvement and approaches to accessibility. The paper adds new insight on an under-studied area, design for hospitals and makes recommendations for a change of approach to user-participation in their design. It highlights the difficulties in applying the methods of user-centred design and Design for All in large projects.  相似文献   
54.
为确保主泵的安全性和可靠性,主泵整机在完成集成设计后需通过试验进行验证。文中介绍了主泵设计与验证的总体思路,提出了主泵工程样机需开展的整机试验项目。基于已有的试验条件,进行了主泵整机集成试验验证方案的优化和可行性分析。分析结果表明,在充分开展主泵各模块、子模块、部件和材料的试验与分析的基础上,可采用小流量试验方案进行主泵整机集成试验验证。   相似文献   
55.
The parameters governing the crystallisation of paracetamol using various conventional techniques has been extensively studied, however the factors influencing the drug crystallisation using spray drying is not as well understood. The aim of this work was to investigate the crystallisation of an active pharmaceutical ingredient through evaporative crystallisation using a spray dryer to study the physicochemical properties of the drug and to use semi-empirical equations to gain insight into the morphology and particle size of the dried powder. Paracetamol solutions were spray dried at various inlet temperatures ranging from 60 °C to 120 °C and also from a series of inlet feed solvent compositions ranging from 50/50% v/v ethanol/water to 100% ethanol and solid-state characterisation was done. The size and morphology of the dried materials were altered with a change in spray drying parameters, with an increase in inlet temperature leading to an increase in particle Sauter mean diameter (from 3.0 to 4.4 µm) and a decrease in the particle size with an increase in ethanol concentration in the feed (from 4.6 to 4.4 µm) as a result of changes in particle density and atomised droplet size. The morphology of the dried particles consisted of agglomerates of individual crystallites bound together into larger semi-spherical agglomerates with a higher tendency for particles having crystalline ridges to form at higher ethanol concentrations of the feed.  相似文献   
56.
Herein, a new mechanism involving Lewis acid-oxygen vacancy interfacial synergistic catalysis for aniline N,N-diethylation with ethanol was proposed, and the SO42−/Ce0.84Zr0.16O2–WO3–ZrO2 catalyst (SCWZ) with both Lewis acid sites and oxygen vacancies was synthesized by the hydrothermal method, which shows better catalytic activity than the reported solid acidic catalysts. Besides, the SO42−/ZrO2 (SZ) and SO42−/WO3–ZrO2 (SWZ) catalysts were also prepared and compared with SCWZ to investigate the synergistic effect of each component. The SO42− and WO3 mainly generate Lewis acid by bonding with ZrO2, which is beneficial for the fracture of the N–H bond in aniline. The Ce0.84Zr0.16O2 solid solution mainly plays a vital role in generating the oxygen vacancies as the interface active species, which can participate in stripping –OH from ethanol, then the carbocation will also be released, which only needs 1.3805 kcal/mol energy, calculated by density functional theory (DFT), to be input. In comparison, the traditional reaction mechanism needs the Brønsted acidic sites to promote the protonation of ethanol, then dehydration and subsequent formation of carbocation followed, and 108.6846 kcal/mol energy needs to be input, which is far higher than that of the new mechanism. The apparent activation energy (Ea) over SCWZ was measured by experiment to be 34.09 kJ/mol, which is much lower than that of SWZ (47.10 kJ/mol) and SZ (54.37 kJ/mol), illustrating comparatively preferable kinetics for SCWZ than that of SWZ and SZ. Besides, the conversion of aniline and selectivity to N,N-diethylaniline over SCWZ reach almost 100% and 73%, respectively. The SCWZ can be renewed for 4 times without rapid deactivation, and the longevity of SCWZ is longer than that of SWZ and SZ, as the loaded SO42− and tetragonal ZrO2 are stabilized by Ce0.84Zr0.16O2 and WO3, respectively.  相似文献   
57.
王彦君 《矿冶》2020,29(4):23-28
通过对紫金山东南矿段铜钼(金)矿床地质矿化特征分析,指出铜钼矿化带主要赋存于花岗闪长斑岩的内外接触带,处于似斑状花岗闪长斑岩的上部,金矿化带赋存在表生氧化带的英安玢岩、隐爆角砾岩中。经过对矿石的组构特征、矿物生成顺序等特征分析,将矿床的成矿演化过程分为斑岩热液期、高硫化浅成低温热液期、表生氧化期三个主要矿化期次,进一步将斑岩热液期分为黑云母-钾长石化阶段、石英-绢云母化阶段、碳酸盐化阶段三个阶段;高硫化浅成低温热液期分为地开石化阶段、明矾石化阶段、硅化阶段三个阶段。研究结果为进一步研究矿床成因提供了依据。  相似文献   
58.
杨斌  孟宪菁  鄂洋  朱湘  尹松 《同位素》2020,33(1):46-52
为了鉴别不同品牌矿泉水标注水源地信息真伪,对11种不同品牌饮用水的氢氧稳定同位素(δD和δ18 O)进行测定。结果表明,水平衡法(GasBench-IRMS)和高温转化法(TC/EA-IRMS)的测定结果一致性较好,两种方法测定6种不同饮用水的δD和δ18 O的平均差异分别为(0.6±1.59)‰和(0.02±0.13)‰。水平衡法需要较长的制备和测定时间,但δD和δ18 O的测定精度明显优于高温转化法。11种饮用水δD和δ18 O变化范围较大,其δD和δ18 O受不同品牌饮用水的水源地降水影响形成明显的地域性。虽然无法区分矿泉水是否由其他类别饮用水伪造,但δD和δ18 O可以为特定区域(如高海拔与沿海地区)以及产地相近的矿泉水水源地鉴别提供依据。  相似文献   
59.
Business process management (BPM) research conceptualizes BPM culture as a type of organizational culture that supports BPM. No quantitative fieldwork has so far examined how such a supporting role manifests itself. We study the relationship between BPM culture, BPM methods, and process performance empirically. Our analysis of multiple survey data sets from a total of 581 practitioners of multiple industries suggests that BPM methods indirectly contribute to process performance by establishing a BPM culture. This finding updates the prevalent assumption that the correct application of methods yields direct performance benefits. We discuss several implications for theory and practice.  相似文献   
60.
徐旭东 《机械制造》2020,58(1):73-75,89
为满足简便检测塑料产品抗冲击强度的需求,研制了垂直冲击试验机。对垂直冲击试验机的结构进行了设计,基于力学原理进行了受力计算,并对工作原理与相对基准设定问题进行了分析。介绍了垂直冲击试验机的操作方法,并进行了规格校验。  相似文献   
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