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71.
Characterization of products from fast and isothermal hydrothermal liquefaction of microalgae 下载免费PDF全文
Julia L. Faeth Phillip E. Savage Jacqueline M. Jarvis Amy M. McKenna Phillip E. Savage 《American Institute of Chemical Engineers》2016,62(3):815-828
We investigated nonisothermal (fast) and nominally isothermal hydrothermal liquefaction (HTL) of Nannochloropsis sp. microalgae for the production of biocrude. Biocrude yields ranged from 36 to 45 wt % (dry weight), with fast HTL with low mass loading giving the highest yield. This condition also gave the biocrude with the lowest heating value, which indicates there are compromises to be made between biocrude quantity and quality. The aqueous phase and biocrude product fractions were characterized using elemental analysis and Fourier transform ion cyclotron resonance mass spectrometry (FT‐ICR MS). This detailed level of analysis identified more than 30,000 unique molecular products. The aqueous phase products included compounds with the same molecular formulae as known herbicides, which may inform efforts in genetic engineering of algae and/or bacteria for cultivation on the aqueous phase. This detailed molecular‐level characterization provides some clues regarding the types of reactions that may take place during HTL. © 2016 American Institute of Chemical Engineers AIChE J, 62: 815–828, 2016 相似文献
72.
Application of β-Sitosterol + γ-Oryzanol-Structured Organogel as Migration Barrier in Filled Chocolate Products 下载免费PDF全文
Alexandra Wendt Karin Abraham Christin Wernecke Julia Pfeiffer Eckhard Flöter 《Journal of the American Oil Chemists' Society》2017,94(9):1131-1140
Oil migration in filled pralines is a phenomenon that is highly correlated with the occurrence of chocolate bloom. In this study the potential to suppress or prevent oil migration by incorporation of sterol/sterolster-structured organogels was evaluated. Different quantities, 2.5 or 14% (w/w), of gel with structurant levels of either 10 or 25% (w/w) were studied in a layered model system. The gel was either a part of the nougat or of the chocolate phase, or as a separate layer. Samples were monitored regularly for a period of 24 weeks at storage temperatures of 10, 18 and 28 °C. The amount of migrated oil was determined via DSC analysis of a surface sample. The results indicate that, despite the additional oil brought into the system via the oleogel, the level of oil found in the chocolate layer is reduced through the presence of the gel. In particular, the three-layer system and gelled chocolate appear to be promising routes to either suppress oil migration or improve nutritional profiles by incorporation of liquid oils. 相似文献
73.
Dr. Jessica S. Kelsey Dr. Tamas Geczy Nancy E. Lewin Dr. Noemi Kedei Colin S. Hill Julia S. Selezneva Christopher J. Valle Wonhee Woo Dr. Inna Gorshkova Dr. Peter M. Blumberg 《Chembiochem : a European journal of chemical biology》2014,15(8):1131-1144
The C1 domain, which represents the recognition motif on protein kinase C for the lipophilic second messenger diacylglycerol and its ultrapotent analogues, the phorbol esters, has emerged as a promising therapeutic target for cancer and other indications. Potential target selectivity is markedly enhanced both because binding reflects ternary complex formation between the ligand, C1 domain, and phospholipid, and because binding drives membrane insertion of the C1 domain, permitting aspects of the C1 domain surface outside the binding site, per se, to influence binding energetics. Here, focusing on charged residues identified in atypical C1 domains which contribute to their loss of ligand binding activity, we showed that increasing charge along the rim of the binding cleft of the protein kinase C δ C1 b domain raises the requirement for anionic phospholipids. Correspondingly, it shifts the selectivity of C1 domain translocation to the plasma membrane, which is more negatively charged than internal membranes. This change in localization is most pronounced in the case of more hydrophilic ligands, which provide weaker membrane stabilization than do the more hydrophobic ligands and thus contributes an element to the structure–activity relations for C1 domain ligands. Coexpressing pairs of C1‐containing constructs with differing charges each expressing a distinct fluorescent tag provided a powerful tool to demonstrate the effect of increasing charge in the C1 domain. 相似文献
74.
Adeel Nasir Peter Rolf Richter Aude Le Bail Viktor Daiker Julia Stoltze Binod Prasad Sebastian Michael Strauch Michael Lebert 《International journal of molecular sciences》2022,23(5)
Euglena gracilis is a photosynthetic flagellate. To acquire a suitable position in its surrounding aquatic environment, it exploits light and gravity primarily as environmental cues. Several physiological studies have indicated a fine-tuned relationship between gravity sensing (gravitaxis) and light sensing in E. gracilis. However, the underlying molecular mechanism is largely unknown. The photoreceptor photoactivated adenylyl cyclase (PAC) has been studied for over a decade. Nevertheless, no direct/indirect interaction partner (upstream/downstream) has been reported for PAC. It has been shown that a specific protein, kinase A (PKA), showed to be involved in phototaxis and gravitaxis. The current study reports the localization of the specific PKA and its relationship with PAC. 相似文献
75.
Anna Carla Culla Corina Vater Xinggui Tian Julia Bolte Tilman Ahlfeld Henriette Bretschneider Alexander Pape Stuart B. Goodman Michael Gelinsky Stefan Zwingenberger 《International journal of molecular sciences》2022,23(6)
To treat critical-size bone defects, composite materials and tissue-engineered bone grafts play important roles in bone repair materials. The purpose of this study was to investigate the bone regenerative potential of hybrid scaffolds consisting of macroporous calcium phosphate cement (CPC) and microporous mineralized collagen matrix (MCM). Hybrid scaffolds were synthetized by 3D plotting CPC and then filling with MCM (MCM-CPC group) and implanted into a 5 mm critical size femoral defect in rats. Defects left empty (control group) as well as defects treated with scaffolds made of CPC only (CPC group) and MCM only (MCM group) served as controls. Eight weeks after surgery, micro-computed tomography scans and histological analysis were performed to analyze the newly formed bone, the degree of defect healing and the activity of osteoclasts. Mechanical stability was tested by 3-point-bending of the explanted femora. Compared with the other groups, more newly formed bone was found within MCM-CPC scaffolds. The new bone tissue had a clamp-like structure which was fully connected to the hybrid scaffolds and thereby enhanced the biomechanical strength. Together, the biomimetic hybrid MCM-CPC scaffolds enhanced bone defect healing by improved osseointegration and their differentiated degradation provides spatial effects in the process of critical-bone defect healing. 相似文献
76.
The concept of data in the humanistic academy carries a heavycultural freight: as a reductionist yet efficient representationof complex textual significance. Far from being an inventionof the digital age, this conception of the role of quantificationhas a prehistory whose terms continue to resonate in moderndebates about digital editing and digitally mediated scholarship.This essay explores these terms and the anxieties they reflect,concluding that digital representation is no less textuallyand methodologically rich, and no less a production of knowledge,than its print counterpart. 相似文献
77.
In this paper, a scheduling problem that occurs in potash mining is introduced, where a block excavation sequence has to be found taking into account a limited number of underground machines as well as safety-related restrictions. The aim is to minimize the maximum completion time of excavations, i.e., the makespan. The resulting problem can be transformed into a hybrid flow shop scheduling problem with reentry, unrelated machines, and job-precedences. A mixed-integer linear model is presented and small-scale instances are solved with CPLEX. In order to tackle medium- and large-scale instances heuristically, a basic and an advanced multi-start algorithm are developed, based on a specific priority rule-based construction procedure. In addition, a modified version of the Giffler and Thompson procedure is applied. Computational experiments are conducted on problem instances derived from real-world data in order to evaluate the performances of the proposed solution procedures. 相似文献
78.
The genomic distance problem in the Hannenhalli–Pevzner (HP) theory is the following: Given two genomes whose chromosomes are linear, calculate the minimum number of translocations, fusions, fissions and inversions that transform one genome into the other. This paper presents a new distance formula based on a simple tree structure that captures all the delicate features of this problem in a unifying way, and a linear time algorithm for computing this distance. 相似文献
79.
Julia Armesto Izabela Lubowiecka Celestino Ordóñez Fernando I. Rial 《Automation in Construction》2009,18(5):559-569
The aim of this paper is to present a methodology for the evaluation of historic timber structures, based on numerical modeling coupled with on site measurements. A method to measure the geometry of structural elements of a timber roof using a photogrammetric modeling procedure is described. In particular, we show the utility of photogrammetric based models when applied to structural analysis by directly introducing 3D geometry files in the preprocessing module of computational software based on the Finite Element Method. The 2D and 3D FEM models of the roof are considered to compare the simple and more complex modeling, and static and dynamic analyses are performed. Both models are prepared using the photogrammetric data. 相似文献
80.
Neiworth Julie J.; Johnson Elizabeth T.; Whillock Katherine; Greenberg Julia; Brown Vanessa 《Canadian Metallurgical Quarterly》2009,123(1):10
To address a controversy in the literature concerning whether monkeys show an aversion to inequity, individuals of a New World monkey species, cotton top tamarins (Saguinus oedipus) were tested in an offering task and in a bartering task. At issue was whether the monkeys rejected rewards because of a violation of expectancy of the preferred reward, or whether they rejected rewards because of a sensitivity to socially mediated inequity. The data from both tasks indicated that the subjects were more likely to reject when preferred rewards were presented, either because of another animal eating the reward (the social condition) or because of rewards being presented but inaccessible. The bartering task led to the only behavioral indication of aversion due specifically to social inequity, which was demonstrated when tamarins' sensitivity to the difference in rewards increased with exposure to other tamarins working to receive the preferred rewards. The results suggest that social inequity aversion will be assessed by tamarins, and possibly by other primates, only under conditions of limited resources and a requirement of work, which may make the situation a bit more competitive and thus drives attention toward both social and reward evaluation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献