Comparative LCA studies of simulated HMF biorefineries from maize and miscanthus as an example of first- and second-generation biomass as a tool for process development

5-Hydroxymethylfurfural (HMF) is a versatile platform chemical for a fossil free, bio-based chemical industry. HMF can be produced by using fructose as a feedstock. Using edible, first-generation biomass to produce chemicals has been questioned in terms of potential competition with food supply. Second-generation biomass like miscanthus could be an alternative. However, there is a lack of information if second-generation lignocellulosic biomass is a more sustainable feedstock to produce HMF. Therefore, a life cycle assessment was performed in this study to determine the environmental impacts of HMF production from miscanthus and to compare it with HMF from high-fructose corn syrup (HFCS). HFCS from either Hungary or Baden-Württemberg (Germany) was considered. Compared to the HFCS biorefineries the miscanthus concept is producing less emissions in all impact categories studied, except land occupation. Overall, the production and usage of second-generation biomass could be especially beneficial in areas where the use of N fertilizers is restricted. Besides, conclusions for the further development of the on-farm biorefinery concept were elaborated. For this purpose, process simulations from a previous study were used. Results of the previous study in terms of TEA and the current LCA study in terms of environmental sustainability indicate that the lignin depolymerization unit in the miscanthus biorefinery has to be improved. The scenario without lignin depolymerization performs better in all impact categories. The authors recommend to not further convert the lignin to products like phenol and other aromatic compounds. The results of the contribution analyses show that the major impact in the HMF production is caused by the auxiliary materials in the separation units and the required heat. Further technical development should focus on efficient heat as well as solvent use and solvent recovery. At this point further optimizations will lead to reduced emissions and costs at the same time.     

Soil amendment with biochar and manure alters wood stake decomposition and fungal community composition

Biochar and manure can be used for sustainable land management. However, little is known about how soil amendments might affect surface and belowground microbial processes and subsequent wood decomposition. In a split-split-split plot design, we amended soil with two rates of manure (whole plot; 0 and 9 Mg ha⁻¹) and biochar (split plot; 0 and 10 Mg ha⁻¹). Wood stakes of three species (hybrid poplar, triploid Populus tomentosa Carr.; aspen, Populus tremuloides Michx.; and pine, Pinus taeda L.) were placed in two positions (horizontally on the soil surface, and inserted vertically in the mineral soil), which served as a substrate for fungal growth. In 3 years, the decomposition rate (density loss), moisture content, and fungal community (via high-throughput sequencing methods) of stakes were evaluated. Results indicated that biochar and/or manure increased the wood stake decomposition rates, moisture content, and operational taxonomic unit abundance. However, the richness and diversity of fungi were dependent on wood stake position (surface > mineral), species (pine > the two Populus), and sample dates. This study highlights that soil amendment with biochar and/or manure can alter the fungal community, which in turn can enhance an important soil process (i.e., decomposition).     

Membrane inlet—ion mobility spectrometry with automatic spectra evaluation as online monitoring tool for the process control of microalgae cultivation

The cultivation of algae either in open raceway ponds or in closed bioreactors could allow the renewable production of biomass for food, pharmaceutical, cosmetic, or chemical industries. Optimal cultivation conditions are however required to ensure that the production of these compounds is both efficient and economical. Therefore, high-frequency analytical measurements are required to allow timely process control and to detect possible disturbances during algae growth. Such analytical methods are only available to a limited extent. Therefore, we introduced a method for monitoring algae release volatile organic compounds (VOCs) in the headspace above a bioreactor in real time. This method is based on ion mobility spectrometry (IMS) in combination with a membrane inlet (MI). The unique feature of IMS is that complete spectra are detected in real time instead of sum signals. These spectral patterns produced in the ion mobility spectrum were evaluated automatically via principal component analysis (PCA). The detected peak patterns are characteristic for the respective algae culture; allow the assignment of the individual growth phases and reflect the influence of experimental parameters. These results allow for the first time a continuous monitoring of the algae cultivation and thus an early detection of possible disturbances in the biotechnological process.     

谷氨酸钠流化床吸附脱色的柱过程研究

以颗粒活性炭(GAC)为吸附剂,采用多柱串联流化床进行味精中和液脱色,对柱过程进行了模拟研究。测定了平衡数据、传质动力学及流体流动参数,建立了具有广泛适应性的,包括颗粒分级、粒度分布、内外扩散及两相返混的宽粒度液固流化床吸附过程模型。对所研究体系的模拟计算与实验结果符合较好。     

Development of fluctuating asymmetry in tail feathers of the barn swallow Hirundo rustica

Fluctuating asymmetry represents usually small, random deviations from symmetry in bilateral morphological characters. The ontogeny of asymmetry in morphological characters may reveal information about developmental processes in a general sense. I studied the development of fluctuating asymmetry in feather characters of the barn swallow Hirundo rustica, that are developed repeatedly during the single annual moult, with the following results. First, the side developing a larger feather was found to be partially biased, as demonstrated by one side consistently developing a larger feather under natural and experimentally induced growth episode events. Second, asymmetric feathers were found to consist of asymmetric daily growth increments, and the size of the increments developing under different environmental conditions were positively correlated. Third, fluctuating asymmetries of feathers developing under different environmental conditions were positively correlated, although the level of asymmetry was larger under adverse environmental conditions. Fourth, individual asymmetries in tail length and growth bar length were unrelated to the duration of the developmental period, although late growth increments were smaller and more symmetric than early increments. These observations suggest that fluctuating asymmetry partially arises as a consequence of a random bias in the feather follicles and differences in environmental conditions during ontogeny of feathers.     

High rate anaerobic digestion of a petrochemical wastewater using biomass support particles

Anaerobic digestion of wastewater from a dimethyl terephthalate plant was studied in continuously stirred tank reactors with plastic net biomass support particles (BSP) at a level of 20% (v/v). The experimental results showed that the BSP system could treat the wastewater at a hydraulic retention time as low as 1.5 d, organic loading as high as 20 kg COD/m3/d and at acidic feed pH as low as 4.5 with 95% COD reduction and biogas production of about 8l/l/d, while the control system without support particles could not treat the wastewater above a 5-d hydraulic retention time, 5 kg COD/m3/d organic loading and a feed pH of 6.0. Thus, augmentation of BSP upgraded the performance of the conventional suspended growth system to an equivalent level to advanced reactors.     

生物分子相互作用分析技术应用实例（四）——实时监测分子生物学过程

利用BIA技术来观察DNA之间的任何相互反应.包括：DNA的延长、连接和退火等.无需任何标记并可测定相互作用的动态参数.     

Studying dynamic process of photosensitization by ESR method

By kinetic methods, functional relation of TAN radical, produced in the process of TEMPONE trapping O2, vs. time during photosensitization was established. Accordingly relative rate constants of generating all kinds of active intermediates through types I and II mechanism of photosensitization can be calculated. Using the formula and experimental results, the relative rate constants of generating O2, O2 and PS2 of three kinds of perylenequinone photosensitizer: HA, HB and CP in DMF-H20 and DMSO-H2O system were calculated, and then the structure-activity relationship of perylenequinone photosensitizer and the relation between photosensitivity and solvent was studied.     

菌紫质光生物分子器件及其超快过程

菌紫质是嗜盐菌紫膜中的一种光能转换蛋白.它具有光致色变和光驱动质子泵功能,其原初光异构化过程极其迅速,可在430fs内完成.由于菌紫质具有一系列独特的光电和光学特性,如对光强的微分响应,高的空间分辨率,高的光灵敏度,高循环次数等,使得它在光电探测,仿视觉系统,人工神经网络,非线性光学及光学信息记录和处理方面有很多重要应用.利用超短脉冲激光技术,高时间分辨光谱学技术及高速取样探测技术,对菌紫质的光循环,原初光异构化,激发态动力学,质子泵机制等方面的研究已取得了许多有意义的结果.     

Cellulase production by Rhizobium

Summary The production of cellulase byRhizobium species was studied.Rhizobium trifolii cellulase was induced by a variety of polysaccharides, including celluloses and hemicelluloses. Cellobiose and myo-inositol also allowed enzyme expression but mannitol prevented it at concentrations higher than 0.25%. Both soluble and insoluble plant root substances moderately stimulated cellulase production byRhizobium trifolii.Most substances tested did not induce the production of cellulases by the slow-growing, cowpea type rhizobia strain CIAT 79. Effective inducers were carboxymethylcellulose, gluconate and myo-inositol.Cellulase production was very low under all conditions tested. In most cases the enzyme activity was loosely bound to the capsular material. The enzyme in fast-growers is an 1,4--D-glucan-4-glucanohydrolase (endo-glucanase EC 3.2.1.4) with specificity for high molecular weight polysaccharides.There was no correlation between infectiveness ofRhizobium trifolii strains and cellulase production. One strain, which lacks the nodulation plasmid, produced cellulase at the same rate as its parental infective strain.