A Simple and Effective Method for the Preparation of Porous Graphene Nanosheets

2015 ◽  
Vol 719-720 ◽  
pp. 123-126
Author(s):  
Jin Sun ◽  
Qing Zhong Xue ◽  
Yong Gang Du ◽  
Fu Jun Xia ◽  
Qi Kai Guo
Keyword(s):  
Large Scale ◽  
Graphene Nanosheets ◽  
Scale Production ◽  
Green Method ◽  
Porous Graphene ◽  
Large Scale Production ◽  
Potential Applications ◽  
One Step ◽  
Autogenous Pressure ◽  
The One

Porous graphene is a collection of graphene-related materials which exhibits properties distinct from those of graphene, and it has widespread potential applications in various fields. Several approaches have been developed to produce porous graphene. However, the large-scale production of porous graphene nanosheets still remains a great challenge. Moreover, the costs of some methods are prohibitive for its commercial production and the processes are too complicated and time-consuming. In this work, we propose a simple and green method by which graphene nanosheets can be etched by sodium hydroxide under autogenous pressure at 180 °C. The morphologies and surface elements of the porous graphene nanosheets and sizes of pores were characterized. It is demonstrated that the one-step etching of graphene nanosheets is an effective method to obtain large-scale porous graphene nanosheets with high and uniform porosity. The pores in the porous graphene nanosheets were 6 nm depth (the same as the thickness of the graphene nanosheets) and 30-50 nm width.

One-step synthesis and assembly of spindle-shaped akaganéite nanoparticles via sonochemistry

CrystEngComm ◽  
2018 ◽  
Vol 20 (21) ◽  
pp. 2989-2995 ◽  
Author(s):  
Weikun Chen ◽  
Pinqiang Dai ◽  
Chunfu Hong ◽  
Chan Zheng ◽  
Weiguo Wang ◽  
...  
Keyword(s):  
Large Scale ◽  
Low Cost ◽  
Scale Production ◽  
Green Method ◽  
Large Scale Production ◽  
One Step

We demonstrate a green method based on sonochemistry for large-scale production of akaganéite nanoparticles and assemblies in low cost.

scholarly journals Solvent-Driven Selectivity on the One-Step Catalytic Synthesis of Manoyl Oxide Based on a Novel and Sustainable “Zeolite Catalyst–Solvent” System

2021 ◽  
Author(s):  
Dimitra Makarouni ◽  
Christos Kordulis ◽  
Vassilis Dourtoglou
Keyword(s):  
Large Scale ◽  
Zeolite Catalyst ◽  
Solvent System ◽  
High Yield ◽  
Scale Production ◽  
Large Scale Production ◽  
One Step ◽  
Catalyst Acidity ◽  
The One ◽  
Potential Precursor

AbstractApplication of a novel “zeolite catalyst–solvent” system for the sustainable one-step synthesis of the terpenoid manoyl oxide, the potential precursor of forskolin and ambrox. Manoyl oxide high-yield and large-scale production over a zeolite catalyst has been infeasible so far, while this system results in 90% yields at 135 °C and atmospheric pressure. Substrate-controlled methodology is used to achieve selectivity. Solvent-driven catalysis is shown, as the activation energy barrier decreases in the presence of appropriate solvents, being 62.7 and 93.46 kJmol−1 for a glyme-type solvent and dodecane, respectively. Finally, catalyst acidity is key parameter for the process. Graphic Abstract

scholarly journals A Review on Additive Manufacturing Possibilities for Electrical Machines

Energies ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1940
Author(s):  
Muhammad Usman Naseer ◽  
Ants Kallaste ◽  
Bilal Asad ◽  
Toomas Vaimann ◽  
Anton Rassõlkin
Keyword(s):  
Additive Manufacturing ◽  
Large Scale ◽  
Three Dimensional ◽  
Electrical Machines ◽  
Electromagnetic Properties ◽  
Scale Production ◽  
Performance Parameters ◽  
Large Scale Production ◽  
One Step ◽  
Manufacturing Techniques

This paper presents current research trends and prospects of utilizing additive manufacturing (AM) techniques to manufacture electrical machines. Modern-day machine applications require extraordinary performance parameters such as high power-density, integrated functionalities, improved thermal, mechanical & electromagnetic properties. AM offers a higher degree of design flexibility to achieve these performance parameters, which is impossible to realize through conventional manufacturing techniques. AM has a lot to offer in every aspect of machine fabrication, such that from size/weight reduction to the realization of complex geometric designs. However, some practical limitations of existing AM techniques restrict their utilization in large scale production industry. The introduction of three-dimensional asymmetry in machine design is an aspect that can be exploited most with the prevalent level of research in AM. In order to take one step further towards the enablement of large-scale production of AM-built electrical machines, this paper also discusses some machine types which can best utilize existing developments in the field of AM.

scholarly journals Foaming of rhamnolipids fermentation: impact factors and fermentation strategies

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Zhijin Gong ◽  
Ge Yang ◽  
Chengchuan Che ◽  
Jinfeng Liu ◽  
Meiru Si ◽  
...  
Keyword(s):  
Production Process ◽  
Large Scale ◽  
Commercial Production ◽  
Impact Factors ◽  
Scale Production ◽  
Large Scale Production ◽  
Foaming Behavior ◽  
Production Strategies ◽  
Potential Applications ◽  
And Control

AbstractRhamnolipids have recently attracted considerable attentions because of their excellent biosurfactant performance and potential applications in agriculture, environment, biomedicine, etc., but severe foaming causes the high cost of production, restraining their commercial production and applications. To reduce or eliminate the foaming, numerous explorations have been focused on foaming factors and fermentation strategies, but a systematic summary and discussion are still lacking. Additionally, although these studies have not broken through the bottleneck of foaming, they are conducive to understanding the foaming mechanism and developing more effective rhamnolipids production strategies. Therefore, this review focuses on the effects of fermentation components and control conditions on foaming behavior and fermentation strategies responded to the severe foaming in rhamnolipids fermentation and systematically summarizes 6 impact factors and 9 fermentation strategies. Furthermore, the potentialities of 9 fermentation strategies for large-scale production are discussed and some further strategies are suggested. We hope this review can further facilitate the understanding of foaming factors and fermentation strategies as well as conducive to developing the more effective large-scale production strategies to accelerate the commercial production process of rhamnolipids.

scholarly journals Efficient Production of l-Ribose with a Recombinant Escherichia coli Biocatalyst

2008 ◽  
Vol 74 (10) ◽  
pp. 2967-2975 ◽  
Author(s):  
Ryan D. Woodyer ◽  
Nathan J. Wymer ◽  
F. Michael Racine ◽  
Shama N. Khan ◽  
Badal C. Saha
Keyword(s):  
Escherichia Coli ◽  
Large Scale ◽  
Active Form ◽  
Apium Graveolens ◽  
Efficient Production ◽  
Scale Production ◽  
Gene Encoding ◽  
Large Scale Production ◽  
One Step ◽  
Rare Sugars

ABSTRACT A new synthetic platform with potential for the production of several rare sugars, with l-ribose as the model target, is described. The gene encoding the unique NAD-dependent mannitol-1-dehydrogenase (MDH) from Apium graveolens (garden celery) was synthetically constructed for optimal expression in Escherichia coli. This MDH enzyme catalyzes the interconversion of several polyols and their l-sugar counterparts, including the conversion of ribitol to l-ribose. Expression of recombinant MDH in the active form was successfully achieved, and one-step purification was demonstrated. Using the created recombinant E. coli strain as a whole-cell catalyst, the synthetic utility was demonstrated for production of l-ribose, and the system was improved using shaken flask experiments. It was determined that addition of 50 to 500 μM ZnCl2 and addition of 5 g/liter glycerol both improved production. The final levels of conversion achieved were >70% at a concentration of 40 g/liter and >50% at a concentration of 100 g/liter. The best conditions determined were then scaled up to a 1-liter fermentation that resulted in 55% conversion of 100 g/liter ribitol in 72 h, for a volumetric productivity of 17.4 g liter−1 day−1. This system represents a significantly improved method for the large-scale production of l-ribose.

scholarly journals Biosynthesis And Structural Characterization of Levan By A Recombinant Levansucrase From Bacillus Subtilis ZW019

2021 ◽  
Author(s):  
Jingyue Wang ◽  
Xinan Xu ◽  
Fangkun Zhao ◽  
Nan Yin ◽  
Zhijiang Zhou ◽  
...  
Keyword(s):  
Large Scale ◽  
Fermentation Broth ◽  
Monosaccharide Composition ◽  
Enzymatic Reactions ◽  
Scale Production ◽  
Large Scale Production ◽  
Nmr Techniques ◽  
One Step ◽  
Activity Of Enzymes

Abstract Purpose: The yield of levan extracted from microbial fermentation broth is low, so in vitro catalytic synthesis of levan by levansucrase is expected to be one of the industrial production approaches of levan. Methods: A recombinant plasmid pET-28a-AcmA-Z constructed in the previous study was used to produce levansucrase. The effects of temperature, pH, and metal ions on the levan formation activity of the levansucrase were investigated. The polymer was analyzed by means of HPIC, FTIR, NMR techniques.Results: The recombinant levansucrase could be easily purified in one step and the purified enzyme had a single band clearly visible in SDS-PAGE. The conditions for enzymatic reactions was optimal at pH 5.2 and 40 ℃, and the activity of enzymes was stimulated by K+ and Ca2+. The yield of levan biosynthesis from 10% (w/v) sucrose with 6.45 U/g sucrose of levansucrase was 30.6 g/L. The molecular weight of the levan was about 1.56×106 Da, as measured by GPC. HPIC analysis showed that the monosaccharide composition of the levan was fructose and glucose. The results of FTIR and NMR analysis indicated that the polymer produced by the recombinant levansucrase was β-(2, 6) levan.Conclusions: The results of this study provide a basis for large-scale production of levan by enzymatic method.

Scalable one-step production of electrochemically exfoliated graphene decorated with transition metal oxides for high-performance supercapacitors

Nanoscale ◽  
2021 ◽  
Author(s):  
Adrián Romaní Vázquez ◽  
Christof Neumann ◽  
Mino Borrelli ◽  
Huanhuan Shi ◽  
Matthias Kluge ◽  
...  
Keyword(s):  
Metal Oxides ◽  
Transition Metal Oxides ◽  
High Performance ◽  
Large Scale ◽  
Wide Field ◽  
Scale Production ◽  
Exfoliated Graphene ◽  
Large Scale Production ◽  
One Step ◽  
Critical Challenge

Graphene and related materials have been widely studied for their superior properties in a wide field of applications. However, large-scale production remains a critical challenge to enable commercial acceptance. Here,...

Sucrose-mediated mechanical exfoliation of graphite: a green method for the large scale production of graphene and its application in catalytic reduction of 4-nitrophenol

2017 ◽  
Vol 41 (20) ◽  
pp. 11969-11978 ◽  
Author(s):  
Sowmya Balasubramanyan ◽  
Sreenikesh Sasidharan ◽  
Raveendran Poovathinthodiyil ◽  
Resmi M. Ramakrishnan ◽  
Binitha N. Narayanan
Keyword(s):  
Ball Milling ◽  
Large Scale ◽  
Catalytic Reduction ◽  
Scale Production ◽  
Green Method ◽  
Mechanical Exfoliation ◽  
Large Scale Production

A simple and green method for the large scale production of graphene by ball-milling of graphite with sucrose is exploited here.

Secondary Industries for Tropical Africa

Africa ◽  
1943 ◽  
Vol 14 (4) ◽  
pp. 170-176 ◽  
Author(s):  
Theresa Cahan
Keyword(s):  
Large Scale ◽  
Good Effect ◽  
Scale Production ◽  
Tropical Africa ◽  
Large Numbers ◽  
Large Scale Production ◽  
Initial Stage ◽  
The One ◽  
Opening Paragraph ◽  
Laborious Method

Opening ParagraphThere is a tendency in some quarters to regard secondary industries as a panacea for all the economic ills of tropical Africa. It would be well at this initial stage to sound a note of warning. In the past, the industrialization of agricultural countries has had two results: one good, one bad. On the one hand, the establishment in a country of labour-saving machinery and large-scale production in place of the old laborious method of making things by hand has led to a rise in the general standard of living within the country in terms of real incomes. On the other hand, the drift of workers to the towns and the herding together of large numbers of people in factories resulted in the sum of social evils associated with the ‘dark satanic mills’: overcrowding, sweated labour, destitution, unemployment, and many more. The problem for tropical Africa to-day is to combine the maximum of the first and good effect with a minimum of the second evil.

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