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71.
血浆单采仪的研究   总被引:2,自引:0,他引:2  
针对血液成分采集、分离、回输的自动化医用仪器设备方面的国内外现状,利用最新的计算机软硬件技术、传感技术、控制理论,开发了拥有自主知识产权的血浆单采仪。经临床实验表明,整机性能优良,值得推广应用。  相似文献   
72.
Key performance indicators have become a common tool in bioprocess development, as they allow an objective and independent rating and ranking of process alternatives screened. A disadvantage of all key performance indicators developed so far is their strong focus on costs, which makes them neglect the influence of the production rate on the profit of the process. But, since both production costs and production rate have an equally strong impact, both should be considered when decisions have to be made. Therefore, two new key performance indicators are introduced in this work, one for batch and one for continuous processing. They combine product yield, purity performance, variable manufacturing costs, and production rate to one objective. Thereby, misguided trade‐offs between these four individual measures can be replaced by one key performance indicator. This ensures a systematic development of biochemical downstream processes.  相似文献   
73.
Workflows are a popular means of automating processes in many domains, ranging from high-level business process modeling to lower-level web service orchestration. However, state-of-the-art workflow languages offer a limited set of modularization mechanisms. This results in monolithic workflow specifications, in which different concerns are scattered across the workflow and tangled with one another. This hinders the design, evolution, and reusability of workflows expressed in these languages. We address this problem through the Unify framework. This framework enables uniform modularization of workflows by supporting the specification of all workflow concerns – including crosscutting ones – in isolation of each other. These independently specified workflow concerns are connected to each other using workflow-specific connectors. In order to further facilitate the development of workflows, we enable the definition of concern-specific languages (CSLs) on top of the Unify framework. A CSL facilitates the expression of a family of workflow concerns by offering abstractions that map well to the concerns' domain. Thus, domain experts can add concerns to a workflow using concern-specific language constructs. We exemplify the specification of a workflow in Unify, and show the definition and application of two concern-specific languages built on top of Unify.  相似文献   
74.
With the rapid increase of lubricant consumption,oil contamination becomes more serious.Biotreatment is an important method to remove oil contamination with some advantages.In this study,acclimatized oilcontaminated soil and used lubricating oil were sampled to isolate lubricant-degrading strains by several methods.51 isolates were obtained and 24-well plates were employed to assess bacterial potential in highthroughput screening.The method was noted for the prominence of oil–water two-phase system with saving chemicals,shortening cycles and lessening workloads.In order to decrease inaccuracy,subculture and resting cells were inoculated into mineral salt medium with 200 μl oil in well plates for the cultivation at 37 °C for 5and 7 days,and the biodegradation potential was characterized by the changes of oil film and cell density.With appropriate evaluation by shaking flask tests,5 isolates were retained for their potentials with the maximum biodegradation from 1500 to 2200 mg · L~(-1)and identified as Acidovorax citrulli,Pseudomonas balearica,Acinetobacter johnsonii(two isolates with different biodegradation potentials)and Acidovorax avenae using 16 S r RNA sequencing analysis.Also,lipase activity was determined using indicator titration and p-nitrophenyl palmitate(p-NPP)methods.The results indicated that only p-NPP was successful to test lipase activity with the range of 1.93–6.29 U · ml~(-1).Although these five strains could degrade 1000 mg · L~(-1)lubricating oil in158–168 h,there existed distinct difference in enzyme activity,which demonstrates that lipase activity could not be used as the criterion to evaluate microbial biodegradation potential for petroleum hydrocarbons.  相似文献   
75.
The paper deals with the modelling and control of aggregated production-inventory systems as described by differential equations. Hitherto, research in the area has been characterized by the approximation of production delays by first-order lags rather than more realistic pure delays. We demonstrate the substantial qualitative differences between these two approaches and thus generate the motivation for the rest of the paper, which tackles pure delay systems. The application of some relatively new design methodologies for delay systems yields four design choices that are tested for their performance over a range of criteria including stability robustness. The investigation is then extended to the model of a supply chain comprising many such productioninventory systems. The mechanism by which disturbances can be transmitted along the supply chain causing disruption and incurring costs to other supply chain echelons is elucidated. A heuristic feedback policy designed adaptively to tune the individual system designs in response to such disturbances is presented.  相似文献   
76.
New avenues to add value to glycerol are currently being explored. One of them is the synthesis of structured lipids through glycerol esterification. In this work we have analyzed the recovery and purification of dicaprin obtained by esterification of glycerol with capric acid (C) in heptane, mediated by Lipozyme RM IM. This is an intermediate step to obtain lipids MLM. In the first stage, the diglyceride synthesis MGM (being G a central HC–OH) was carried out. When M = C, the diglyceride is CGC. Recovery of the diglyceride CGC is required to carry out the esterification of the sn-2 position with palmitic acid (P), thus obtaining the triglyceride CPC. Different solvents were evaluated using Ecofac 1.0 (a molecular design software solvent) through a theoretical approach to explore the best solvents for the acylglycerides separation. Then, the performance of the selected solvents to separate dicaprin from mono and tricaprin was experimentally studied in a liquid–liquid extraction process. Previously, the remaining fatty acid had been neutralized. With liquid–liquid extraction in three simple steps, using ethanol/water, 94 % of the dicaprin obtained by enzymatic esterification was recovered with a purity of 89 % (wt%). It was also possible to obtain dicaprin with a purity of 97 % but with a yield of 56 %.  相似文献   
77.
Magnetic ionic liquids (MIL) are extensively used in extraction and catalytic processes. Here, a series of MIL, i.e., 1‐n‐butyric acid‐3‐methylimidazolium chloride/xFeCl3 ([C3H6COOHmim]Cl/xFeCl3; x = 0.5, 1, 1.5, 2), were synthesized and characterized by infrared spectroscopy, visible absorption spectrometry, and electrospray ionization mass spectrometry. The MIL [C3H6COOHmim]Cl/2FeCl3 was found to be highly active for the extraction and catalytic oxidative desulfurization of a model oil under mild conditions. Of note, the removal of benzothiophene, which has been regarded as a refractory aromatic sulfur compound, could be achieved at up to 100 % in 10 min. After reaction, the MIL could be easily separated from the model oil by applying an external magnetic field, due to its paramagnetic properties.  相似文献   
78.
The focus of this paper is on identification of typical graphical user interface (GUI) programming concerns. As opposed to some other proposals available in the literature that indicate GUI programming concerns by simple intuition, we have conducted a systematic empirical analysis to derive our proposal. It included an analysis of an existing application programming interface (API), its use in industrial projects, and an analysis of the requirements and issues reported during software maintenance. In addition, we have evaluated more than 50 GUI frameworks and APIs and proved usefulness and generality of our classification of concerns. As an additional proof of applicability of the proposed classification, we have refactored the inheritance hierarchy of the selected GUI API using concern-oriented interfaces. We have implemented a supporting tool that complements the developed API and supports its concern-oriented use. The evaluation of the refactored API showed positive effects on API usability.  相似文献   
79.
In present work, the oils were treated by saponification procedure to release fatty acids from triglycerides to obtain free fatty acids (FFA) enriched oils and glycerol. Phase equilibria data for systems FFA enriched rapeseed oil–CO2, FFA enriched corn germ oil–CO2 and FFA enriched borage oil–CO2 were determined at temperatures 35, 45, 65 and 85 °C, and in pressure range from 100 to 550 Bar. Experiments using FFA enriched oils were performed using high-pressure variable–volume view cell, where phase inversions were also observed at temperatures 35 and 45 °C. Samples from liquid and vapor phases were analyzed by gas chromatography for the content of free fatty acids, and based on obtained data; the distribution coefficients and the separation factors between FFA and glycerol were calculated.  相似文献   
80.
The coalescence of an aqueous droplet at an oil-water interface under an electric field has been investigated, with a view to quantify conditions that give rise to secondary droplet formation. Two patterns of drop-interface coalescence may occur: complete coalescence and partial coalescence. The former is obviously the desirable pattern for industrial coalescers. However in practice, the process of coalescence could actually produce smaller droplets, which become more difficult to remove, and hence undesirable. This is caused by either necking, due to extensive elongation of the droplet, or reaction to a fast and energetic coalescence and is referred to as partial coalescence. The volume of the droplets formed in this way has been analyzed as a function of the initial droplet size, electric field strength and the distance between the droplet and the interface. The expansion speed of the neck connecting the droplet and interface at the beginning of the pumping process has also been quantified. These results are useful in optimizing the electro-coalescence process.  相似文献   
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