A method for total Hg determination in fish tissue using cold vapor capacitively coupled plasma microtorch optical emission spectrometry was evaluated. The low-cost miniaturized analytical system includes a low power plasma microtorch (10 W) and low Ar consumption (150 ml min⁻¹) and a QE65Pro microspectrometer as detector. Lyophilized fish tissues were microwave-assisted digested in HNO₃–H₂O₂mixture, brought in 5 % (v/v) HCl, then Hg vapor was chemically generated with 20 % SnCl₂solution stabilized in 15 % (v/v) HCl. The figures of merit of the proposed method were evaluated by analyzing certified reference materials and test samples and compared to those of the well-established thermal decomposition atomic absorption spectrometry method. The analytical characteristics (limits of detection and quantification, precision, and accuracy) comply with requirements for Hg determination in seafood set out in Decisions 2007/333/EC and 2002/657/EC. The limits of detection and quantification of the proposed method were 3 and 9 μg kg⁻¹Hg in dry mass, similar to those in thermal decomposition atomic absorption spectrometry. The precision was between 1.8 and 5.5 % for concentrations in the range 0.18–0.76 mg kg⁻¹Hg, while the accuracy was 99.7 ± 3.0 %. The significance tests revealed no difference between the results obtained by the two methods. The proposed miniaturized spectrometric equipment could be the subject of prototyping as low-cost instrumentation for designed applications in seafood control.
The advent of advanced therapies in the pharmaceutical industry has moved the spotlight into virus-like particles and viral vectors produced in cell culture holding great promise in a myriad of clinical targets, including cancer prophylaxis and treatment. Even though a couple of cases have reached the clinic, these products have yet to overcome a number of biological and technological challenges before broad utilization. Concerning the manufacturing processes, there is significant research focusing on the optimization of current cell culture systems and, more recently, on developing scalable downstream processes to generate material for pre-clinical and clinical trials. We review the current options for downstream processing of these complex biopharmaceuticals and underline current advances on knowledge-based toolboxes proposed for rational optimization of their processing. Rational tools developed to increase the yet scarce knowledge on the purification processes of complex biologicals are discussed as alternative to empirical, “black-boxed” based strategies classically used for process development. Innovative methodologies based on surface plasmon resonance, dynamic light scattering, scale-down high-throughput screening and mathematical modeling for supporting ion-exchange chromatography show great potential for a more efficient and cost-effective process design, optimization and equipment prototyping.
Lian Wenxiang, Gansu Agricultural University, Lanzhou(China), College of Engineering, Wei Hongan, Gansu Agricultural University, Lanzhou(China), College of Engineering, and Shao Shilu, Gansu Agricultural University, Lanzhou(China), College of Engineering
Journal of Gansu Agricultural University, Oct. 2010, v.45(5) p.129-133.
Agricultural machinery and equipment, HARVESTERS, POTATOES, EQUIPMENT, MATERIEL DE RECOLTE, POMME DE TERRE, MATERIEL, COSECHADORAS, PAPA, and EQUIPO
Resume(Zh,En) 14 ref. 对4U-1400FD型马铃薯联合收获机,运用虚拟样机方法Pro/E绘制收获机三维实体图,应用ANSYS有限元分析软件,对其机架建立有限元模型,分析了收获机在以3～4.83km・h. 1速度作业时机架的应力分布、最大应力及其产生部位.分析计算结果与样机试验结果表明：机架的结构设计合理,强度储备足够,工作安全可靠.[著者文摘] In the design of 4U-1400FD potato combine harvester,the three-dimensional solid figure of the machine was drawn by the virtual prototyping methods Pro/E and the finite element model was established with ANSYS software.The stress distribution,maximum stress and resulting parts were analyzed in the working speed of 3km・h. 1 to 4.83km・h. 1.The calculation and the prototype test results showed that the frame structure design was reasonable,the reserve of strength was adequate,and it could work safely and reliably.[著者文摘]