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81.
在2004年汉诺威博览会上,时代(Zeitlauf)公司首次展出了具有实际意义的行星减速器结构系列“Performax”。该系列由于高运转平稳性、高功率密度和高寿命,在市场上脱颖而出。结构系列一直是按照模块系统建造的,从而明显地减少了必需的组件数和加工步骤。 相似文献
82.
83.
Hagren V von Lode P Syrjälä A Korpimäki T Tuomola M Kauko O Nurmi J 《International journal of food microbiology》2008,125(2):158-161
We describe a system consisting of rapid sample enrichment and homogeneous end-point PCR analysis that enables the detection of Salmonella in various food matrices in 8 h. Sample preparation starts with 6 h enrichment step in supplemented broth, after which Salmonella cells are collected with immunomagnetic particles. The particles are washed and dispensed to ready-to-use PCR reaction vessels, which contain dried assay-specific reagents and an internal amplification control. PCR is performed with a novel instrument platform utilising the sensitive label technology of time-resolved fluorometry. Qualitative assay results are automatically interpreted and available in 45 min after sample addition. The overall accuracy, sensitivity and specificity of the Magda CA Salmonella system were 99.1%, 98.4% and 100.0%, respectively, based on the evaluation of 107 samples (beef, pork, poultry and ready-to-eat meals) artificially contaminated with sub-lethally injured Salmonella cells. 相似文献
84.
This study explores the emergence of the living labs movement based on a literature review and interviews with experts acquainted with early living labs. The study contributes to the growing literature on innovation through living labs by addressing a research gap on why and how this movement is evolving. So doing, the study discusses the emergence of living labs from the perspectives of: (i) early living lab pioneers; (ii) early living lab activities in Europe, especially at Nokia Corporation; (iii) EU funding that supported the creation of living labs; (iv) national living lab networks; and (v) the multinational European Network of Living Labs (ENoLL). Moreover, upon highlighting major events in the emergence of living labs, the study identifies three consecutive phases of the global living lab movement: (i) toward a new paradigm; (ii) learning from experience; and (iii) professional living labs. 相似文献
85.
ABSTRACTIn just one decade, social media have moved from being marginal phenomena to having three billion active monthly users globally in 2017. We use a large representative sample to study which company characteristics are associated with the early adoption of social media. Our findings suggest that digital orientation (outside social media), innovativeness, external collaboration in marketing and sales, and orientation towards consumer markets all increase a company’s probability of adopting social media. In addition, larger and younger companies are more likely to be early movers. Overall, business use of social media has only reached its early maturity; thus, it still has plenty of room to grow. 相似文献
86.
Kamwilaisak Khanita Siripanee Sutathip Jutakridsada Pasakorn Pimsawat Nutsupa Chokesawatanakit Nuttaporn Rittiwut Kanokwan Theerakulpisut Somnuk Sillanpääe Mika Chindaprasirt Prinya 《Clean Technologies and Environmental Policy》2022,24(8):2517-2530
Clean Technologies and Environmental Policy - In this work, the porosity enhancement of activated carbon by hydrolyzed lignin extracted from black liquor was studied. Lignin was treated before... 相似文献
87.
Panu Tanninen Ville Leminen Sami Matthews Mika Kainusalmi Juha Varis 《Packaging Technology and Science》2018,31(5):369-376
Three‐dimensional forming of paperboard is commonly done by a press forming process, which has been widely researched. However, the process cycle of the press forming of paperboard trays has not yet been completely optimized due to limited adjustability and unsophisticated mechanical structure of commonly used forming equipment. The object of this study is to optimize the force curve of stroke to improve product quality without compromising the production rate using LUT Adjustable Packaging Line prototype for practical evaluation of formability and multibody dynamics software MSC Adams for simulation. Several process parameters were investigated with different process cycles to study their effect on the quality of the formed products. With optimized male mould speed, acceleration and speed of the blank could be reduced, which led to significantly reduced rupturing tendency without compromising the production speed. It was also found that a constant blank holding force should be used to achieve acceptable tray quality, although this results in a significantly increased surface pressure applied to the formed substrate. It was also discovered that a novel male mould attachment, which included a pressing force adjustment system that utilized a spring set with an adjustable preload, made it possible to control the force distribution between different forming tools during the dwelling phase of the process cycle in an improved way. Utilization of the method used in this paper leads to a better tray quality without compromising the production efficiency. Furthermore, this can increase the number of possible package applications for sustainable materials, such as paperboard. 相似文献
88.
89.
Adrian Moreno Javier Delgado-Lijarcio Juan C. Ronda Virginia Cádiz Marina Galià Mika H. Sipponen Gerard Lligadas 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(7):2205672
The design of stimuli-responsive lignin nanoparticles (LNPs) for advanced applications has hitherto been limited to the preparation of lignin-grafted polymers in which usually the lignin content is low (<25 wt.%) and its role is debatable. Here, the preparation of O2-responsive LNPs exceeding 75 wt.% in lignin content is shown. Softwood Kraft lignin (SKL) is coprecipitated with a modified SKL fluorinated oleic acid ester (SKL-OlF) to form colloidal stable hybrid LNPs (hy-LNPs). The hy-LNPs with a SKL-OlF content ranging from 10 to 50 wt.% demonstrated a reversible swelling behavior upon O2/N2 bubbling, increasing their size – ≈35% by volume – and changing their morphology from spherical to core-shell. Exposition of hy-LNPs to O2 bubbling promotes a polarity change on lignin-fluorinated oleic chains, and consequently their migration from the inner part to the surface of the particle, which not only increases the particle size but also endows hy-LNPs with enhanced stability under harsh conditions (pH < 2.5) by the hydration barrier effect. Furthermore, it is also demonstrated that these new stimuli-responsive particles as gas tunable nanoreactors for the synthesis of gold nanoparticles. Combining a straightforward preparation with their enhanced stability and responsiveness to O2 gas these new LNPs pave the way for the next generation of smart lignin-based nanomaterials. 相似文献
90.
Lead(II)‐ion removal by ethylenediaminetetraacetic acid ligand functionalized magnetic chitosan–aluminum oxide–iron oxide nanoadsorbents and microadsorbents: Equilibrium,kinetics, and thermodynamics 下载免费PDF全文
Novel nanosized and microsized chitosan–Al2O3–Fe3O4 (CANF and CAMF, respectively) adsorbents were functionalized with ethylenediaminetetraacetic acid (EDTA) ligands and applied to the removal of Pb(II) ions. The prepared adsorbents were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and Brunauer–Emmett–Teller analysis, and their adsorption potentials were investigated with Pb(II) as a target metal under various experimental conditions. Our results show that the EDTA functionalization of CANF and CAMF increased their adsorption capacities about 31.5 and 38 times, respectively. The optimum dosage obtained was 1.0 g/L for both EDTA‐functionalized adsorbents, and the maximum adsorption took place at pH = 5.3. The kinetic results revealed that the adsorption obeyed the pseudo‐second‐order model and that the pore diffusion process played a key role in the adsorption kinetics. Also, the results of equilibrium isotherms indicate the good fit of the experimental data by the Langmuir isotherm model under the studied concentration and temperature ranges, and the adsorptions of Pb(II) ions from aqueous solution followed the monolayer coverage of the adsorbents. The maximum Pb(II)‐ion adsorption capacities of EDTA–CANF and EDTA–CAMF were 160 and 157 mg/g, respectively. These metal‐loaded adsorbents could be readily recovered from aqueous solution by magnetic separation and reused. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44360. 相似文献