scholarly journals Cu-Catalyzed, Mn-Mediated Propargylation and Allenylation of Aldehydes with Propargyl Bromides

2021 ◽  
Author(s):  
Rongli Zhang ◽  
Yanping Xia ◽  
Yuchen Yan ◽  
Lu Ouyang
Keyword(s):  
Large Scale ◽  
Standard Condition ◽  
Product Variety ◽  
Propargyl Alcohol ◽  
Selective Method ◽  
High Yields

Abstract A simple, practical, and high chemo-selective method for the synthesis of propargyl alcohol and allenyl alcohols via Cu-catalyzed, Mn-mediated propargylation and allenylation of aldehydes with propargyl bromides has been established. When 3-bromo-1-propyne was conducted under the standard condition, the aldehydes were transformed to the corresponding propargylation products completely, while when 1-bromo-2-pentyne was used, allenic alcohol was the only product. Variety of homopropargyl alcohols and allenyl alcohols were obtained in high yields and the reaction is compatible with broad substrate scopes. In addition, the large-scale reaction could also be proceeded smoothly indicating the potential synthetic applications of this transformation.

scholarly journals A simple and efficient automated microvolume radiosynthesis of [18F]Florbetaben

2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Ksenia Lisova ◽  
Jia Wang ◽  
Philip H. Chao ◽  
R. Michael van Dam
Keyword(s):  
Large Scale ◽  
Solid Phase ◽  
Acetonitrile Solution ◽  
Synthesis Methods ◽  
Pet Tracers ◽  
Molar Activity ◽  
Alternative Approaches ◽  
High Yields ◽  
Sufficient Concentration

Abstract Background Current automated radiosynthesizers are generally optimized for producing large batches of PET tracers. Preclinical imaging studies, however, often require only a small portion of a regular batch, which cannot be economically produced on a conventional synthesizer. Alternative approaches are desired to produce small to moderate batches to reduce cost and the amount of reagents and radioisotope needed to produce PET tracers with high molar activity. In this work we describe the first reported microvolume method for production of [18F]Florbetaben for use in imaging of Alzheimer’s disease. Procedures The microscale synthesis of [18F]Florbetaben was adapted from conventional-scale synthesis methods. Aqueous [18F]fluoride was azeotropically dried with K2CO3/K222 (275/383 nmol) complex prior to radiofluorination of the Boc-protected precursor (80 nmol) in 10 μL DMSO at 130 °C for 5 min. The resulting intermediate was deprotected with HCl at 90 °C for 3 min and recovered from the chip in aqueous acetonitrile solution. The crude product was purified via analytical scale HPLC and the collected fraction reformulated via solid-phase extraction using a miniature C18 cartridge. Results Starting with 270 ± 100 MBq (n = 3) of [18F]Fluoride, the method affords formulated product with 49 ± 3% (decay-corrected) yield,> 98% radiochemical purity and a molar activity of 338 ± 55 GBq/μmol. The miniature C18 cartridge enables efficient elution with only 150 μL of ethanol which is diluted to a final volume of 1.0 mL, thus providing a sufficient concentration for in vivo imaging. The whole procedure can be completed in 55 min. Conclusions This work describes an efficient and reliable procedure to produce [18F]Florbetaben in quantities sufficient for large-scale preclinical applications. This method provides very high yields and molar activities compared to reported literature methods. This method can be applied to higher starting activities with special consideration given to automation and radiolysis prevention.

scholarly journals Performance of Strawberry Varieties Developed for Perennial Matted-Row Production in Annual Plasticulture in a Cold Climate Region

Agronomy ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1407
Author(s):  
Courtney A. Weber
Keyword(s):  
Large Scale ◽  
Fruit Size ◽  
Weather Conditions ◽  
Cold Climate ◽  
Annual Production ◽  
High Yield ◽  
Production Cycle ◽  
Late Season ◽  
Berry Weight ◽  
High Yields

Annual plasticulture production of strawberries promises superior weed control, fruit quality and yields. However, strawberry varieties adapted for perennial, matted-row production and local markets in cold climate regions have not been widely tested for adaptation to an annual production cycle. Productivity of seven short-day varieties developed for matted-row and/or annual production was examined in an annual plasticulture system in two consecutive trials in central NY (lat. 42.87° N, long. 76.99° W) harvested in 2013 and 2014. ‘Flavorfest’ demonstrated good performance in Trial 1 with high yield (390 g/plant) and large fruit size (13.9 g mean berry weight). ‘Jewel’ was shown to be well adapted to the annual plasticulture system with consistently high yields (330 and 390 g/plant) that equaled or surpassed other varieties and had moderate fruit size. ‘Chandler’ performed similarly to previous trials conducted in warmer regions with yield (340 g/plant) and fruit size (9.8 g mean berry weight) similar to ‘Jewel’. ‘Clancy’ yielded less but was consistent from year to year. The late season varieties Seneca and Ovation showed marked variability between years, possibly due to drastically different temperatures during flowering and fruit development in Trial 1 compared to Trial 2. High temperatures in Trial 1 likely caused higher early fruit yield, a compressed season and a precipitous decline in fruit size in the later season, thus reducing yield in the late season. Survival after a second dormant period was poor resulting in a small second harvest and reduced fruit size. Overall, the system demonstrated many of the expected benefits but may be more sensitive to weather conditions in the region. While many varieties developed for matted-row production may work well in an annual plasticulture system, not all varieties are equally adapted. Performance of each variety should be determined independently before large scale adoption by growers.

Improved efficiency of liquid-phase shear exfoliation of expanded graphite with bifunctional additives of mica plates

2021 ◽  
Author(s):  
Bin Liang ◽  
Kangwei Liu ◽  
Peng Liu ◽  
Guangyao Zhao ◽  
Weisheng Pan ◽  
...  
Keyword(s):  
Liquid Phase ◽  
Large Scale ◽  
Expanded Graphite ◽  
Scale Production ◽  
Large Scale Production ◽  
High Yields

Liquid-phase shear exfoliation (LPSE) has been a potential way of large-scale production of good-quality graphene. How to obtain few-layer (<10) graphene with large lateral sizes and high yields remains a...

Accommodating Students with Disabilities on Large-Scale Tests: An Experimental Study

1998 ◽  
Vol 64 (4) ◽  
pp. 439-450 ◽  
Author(s):  
Gerald Tindal ◽  
Bill Heath ◽  
Keith Hollenbeck ◽  
Patricia Almond ◽  
Mark Harniss
Keyword(s):  
General Education ◽  
Students With Disabilities ◽  
Large Scale ◽  
Standard Condition ◽  
Standard Test ◽  
Test Administration ◽  
General Education Students ◽  
Trained Teacher ◽  
Reading And Math ◽  
Math Test

In this study, fourth-grade special and general education students took a large-scale state-wide test using standard test administration procedures and two major accommodations addressing response conditions and test administration. On both reading and math tests, students bubbled in answers on a separate sheet (the standard condition) for half the test and marked the test booklet directly (the accommodated condition) for the other half of the test. For a subgroup of students, the math test was read to them by a trained teacher. Although no differences were found in the response conditions, an interaction was found in the test administration conditions (orally reading the test), supporting this accommodation for students with disabilities.

scholarly journals Conversion of Fructose to HMF in a Continuous Fixed Bed Reactor with Outstanding Selectivity

Molecules ◽  
2018 ◽  
Vol 23 (7) ◽  
pp. 1802 ◽  
Author(s):  
Eric Weingart ◽  
Sarah Tschirner ◽  
Linda Teevs ◽  
Ulf Prüße
Keyword(s):  
Large Scale ◽  
Continuous Process ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Water Addition ◽  
Batch Systems ◽  
Formation Conditions ◽  
High Yields ◽  
Optimized Conditions ◽  
By Products

5-Hydroxymethylfurfural (HMF) is a very promising component for bio-based plastics. Efficient synthesis of HMF from biomass is still challenging because of fast degradation of HMF to by-products under formation conditions. Therefore, different studies, conducted mainly in monophasic and biphasic batch systems with and without water addition have been published and are still under investigation. However, to produce HMF at a large scale, a continuous process is preferable. Until now, only a few studies have been published in this context. In this work, it is shown that fluorous alcohol hexafluoroisopropanol (HFIP) can act as superior reaction solvent for HMF synthesis from fructose in a fixed bed reactor. Very high yields of 76% HMF can be achieved in this system under optimized conditions, whilst the catalyst is very stable over several days. Such high yields are only described elsewhere with high boiling reaction solvents like dimethylsulfoxide (DMSO), whereas HFIP with a boiling point of 58 °C is very easy to separate from HMF.

Cultivation and Environmental Impact of Corn

2019 ◽  
Author(s):  
Emerson Nafziger
Keyword(s):  
Large Scale ◽  
Fossil Fuels ◽  
Environmental Cost ◽  
High Yield ◽  
Grass Species ◽  
Corn Production ◽  
Environmental Consequences ◽  
External Sources ◽  
Use Efficiency ◽  
High Yields

Corn ranks first among crops in quantity produced globally, owing to its high yield and to its value as a food for humans and domestic animals. While its water-use efficiency is high compared to that of other crops, the production of high corn yields requires a great deal of water; the availability of water largely determines where the crop is grown. As a high-yielding grass species, corn also requires a substantial supply of nutrients (especially nitrogen) from external sources, including manufactured fertilizers and organic materials such as animal or green manures. This, along with the need to manage soils, weeds, insects, and diseases, makes corn production environmentally consequential. Corn captures large quantities of sunlight energy through photosynthesis, but its production requires large external inputs of energy, coming mostly (in mechanized production) from fossil fuels. So even though the crop’s high yields moderates the environmental cost per unit of grain produced, minimizing the external environmental consequences of large-scale corn production is an important goal in the quest for greater sustainability of production of this important crop.

scholarly journals A purification procedure for the soluble cytochrome oxidase and some other respiratory proteins from Pseudomonas aeruginosa

1976 ◽  
Vol 157 (2) ◽  
pp. 423-430 ◽  
Author(s):  
S R Parr ◽  
D Barber ◽  
C Greenwood
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Cytochrome Oxidase ◽  
Large Scale ◽  
Sodium Ascorbate ◽  
Small Scale ◽  
Purification Procedure ◽  
Electron Mediator ◽  
Respiratory Proteins ◽  
High Yields ◽  
Cytochrome C551

The production of the soluble cytochrome oxidase/nitrite reductase in the bacterium Pseudomonas aeruginosa is favoured by anaerobic conditions and the presence of KNO3(20g/l) in the culture medium. Of three methods commonly used for the disruption of bacterial suspensions (ultrasonication, liquid-shear homogenization and glass-bead grinding), sonication proved the most efficient in releasing the Pseudomonas cytochrome oxidase. A polarographic assay of Pseudomonas cytochrome oxidase activity with sodium ascorbate as substrate and NNN‘N’-tetramethyl-p-phenylenediamine dihydrochloride as electron mediator is described. A purification procedure was developed which can be used on the small scale (40-litre cultures) or the large scale (400-litre cultures) and provides high yields of three respiratory-chain proteins, Pseudomonas cytochrome oxidase, cytochrome c551 and azurin, in a pure state. A typical preparation of 250g of Ps.aeruginosa cell paste yielded 180mg of Pseudomonas cytochrome oxidase, 81 mg of Pseudomonas cytochrome c551 and 275mg of Pseudomonas azurin.

The role of hierarchical production planning in food manufacturing SMEs

2015 ◽  
Vol 35 (10) ◽  
pp. 1362-1385 ◽  
Author(s):  
Seamus O'Reilly ◽  
Anita Kumar ◽  
Frédéric Adam
Keyword(s):  
Decision Making ◽  
Production Planning ◽  
Large Scale ◽  
Product Variety ◽  
Food Manufacturing ◽  
Content Type ◽  
Hierarchical Production Planning ◽  
Trade Offs ◽  
Internal Integration

Purpose – In recent years there has been an increasing interest in make-to-stock and make-to-order combined strategies in food manufacturing operations. However, most scholarly work to-date has neglected the role of hierarchical production planning (HPP) in guiding small- and medium-sized enterprise (SME) implementation of such strategies. The purpose of this paper is to address food SME manufacturers’ readiness to adopt such strategies, in terms of internal integration and their capability to adopt formalised planning approaches. Design/methodology/approach – This study adopted an action research methodology to explore the potential impact of HPP in SME food manufacturers. Selected companies had identified product variety management as a challenge and also had recognised the need to enhance internal integration. Given this, the research team, from a theoretical perspective, proposed the use of HPP set within a broader decision-making conceptual framework to improve internal integration and planning. Findings – This paper adopts the fundamental position that HPP provides a useful framework in the establishment of strategic and tactical level constraints and priorities which then act as specific guides at the operational level, and presents empirical evidence in a food SME manufacturing context. In the cases the authors studies, the cascading effect of this decision-making framework focused attention on key metrics, encouraged greater internal integration and delivered tangible, significant improvements in performance. This was greatly facilitated by the provision of new key data on the cost of certain managerial trade-offs which these firms faced. Originality/value – SMEs are of a scale that requires a formalised planning approach; however production planning systems are typically designed for large scale enterprises. This paper addresses the need of SMEs in this regard. Well-established supply chain metrics were used to establish the benefits of both HPP and resulting improvement in internal integration and beyond, in terms of improvement in the quality of planning decisions.

scholarly journals A CONCEPTUAL STUDY ON THE IMPACT OF ONLINE SPENDING BEHAVIOR TOWARDS E-COMMERCE

2021 ◽  
Vol 3 (9) ◽  
pp. 172-183
Author(s):  
Shafira Noor Ashifa ◽  
Raden Aswin Rahadi
Keyword(s):  
Large Scale ◽  
Product Variety ◽  
Physical Contact ◽  
Consumption Behavior ◽  
Social Restriction ◽  
Positive Rate ◽  
Spending Behavior ◽  
Conceptual Study ◽  
The Impact ◽  
The Relationship

As the covid-19 positive rate keeps increasing, the Indonesian government established a large-scale social restriction, or Pembatasan Sosial Berskala Besar (PSBB) to reduce the virus spread. At the same time e-commerce use is rapidly increasing, offering convenience to customers. With the existence of e-commerce, there is no need for physical contact. The objective of this paper is to determine the relationship between online spending and e-commerce use during a pandemic. The data used for this study was gathered from existing literature such as journals, books, and research papers that are related to the research topics. The scope & limitations are the covid-19 is unpredictable, the pandemic might give a different effect on consumption behavior in the future. The research was finally able to create a clear conceptual framework on the relationship between online spending behavior and e-commerce use based on the literature review. According to the framework, perceived behavioral cost, product variety, product comparison, application usability, safeness and healthiness, and recession in Indonesia would all have a direct impact on e-commerce use during a pandemic.

scholarly journals Biotechnological Valorization of Pectinolytics and Their Industrial Applications: A Review

2014 ◽  
Vol 9 (11) ◽  
pp. 1934578X1400901 ◽  
Author(s):  
Muhammad Irshad ◽  
Muhammad Asgher ◽  
Zahid Anwar ◽  
Aftab Ahmad
Keyword(s):  
Large Scale ◽  
Value Added ◽  
Cost Effective ◽  
Industrial Applications ◽  
Green Biotechnology ◽  
A Value ◽  
Physico Chemical ◽  
Target Yield ◽  
High Yields ◽  
Agricultural Materials

In the last several years, in serious consideration of the worldwide economic and environmental issues there has been an increasing research interest in the value of naturally occurring bio-sourced materials. Agro-industrial based biomass comprised of pectin is an inexpensive, renewable, abundant natural resource that could be utilized for large-scale and cost-effective production of natural products i.e., pectinolytics. Pectinolytics are one of the most widely distributed enzymes in bacteria, fungi and plants. From ancient times to date, many methods have been introduced to improve the optimization of pectinolytics to obtain high yields of maximal purity. To expand the range of natural bio-resources the rapidly evolving tools of biotechnology can lower the conversion costs and also enhance target yield of the product of interest. This green biotechnology presents a promising approach to convert most of the agricultural materials into a value-added product with multiple applications. Major advances have already been achieved in recent years in order to obtain high levels of purity with optimal yields. The present review begins with an overview of pectinolytics and their physico-chemical features, and their specific role with classification based on pectic materials. Information is also given on the culture influences and potential sources of pectinolytics, followed by a brief summary of various industrial and biotechnological applications and future considerations.

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