scholarly journals Fermentable sugars from Lupinus rotundiflorus biomass by concentrated hydrochloric acid hydrolysis

BioResources ◽  
2010 ◽  
Vol 6 (1) ◽  
pp. 344-355
Author(s):  
J. Jesús Vargas Radillo ◽  
Mario A. Ruiz-López ◽  
Ramón Rodríguez Macías ◽  
Lucía Barrientos Ramírez ◽  
Pedro M. García-López ◽  
...  
Keyword(s):  
Hydrochloric Acid ◽  
Plant Biomass ◽  
Lignin Content ◽  
Low Cost ◽  
General Interest ◽  
Second Stage ◽  
Ample Supply ◽  
Wide Availability ◽  
Fermentable Carbohydrates ◽  
High Yields

It is of general interest to produce fermentable carbohydrates from plant biomass. However, obtaining monosaccharides requires some effort, due to the intricate structure of the cell wall lignocellulosic complex. The aim of this study was to apply a simple two-stage hydrolysis process, using only concentrated hydrochloric acid, to generate fermentable carbohydrates from L. rotundiflorus biomass. First and second stage acid concentrations were 32% and 42.6%. Total monosaccharide yields with respect to dry matter after the first stage, second stage, and the overall process, were 27.5%, 21.0% and 48.4%, respectively. Xylose was the main first stage carbohydrate in the hydrolysate, followed by glucose, arabinose, and galactose. After the second stage only glucose and a small amount of xylose were detected. The polysaccharide hydrolysis was eased by overall low lignin content. Some advantages of this method were the use of a single hydrolyzing agent and that most of the polysaccharides were hydrolyzed in reasonably high yields. The acceptable yield, relative simplicity, the use of most of the biomass along with the wide availability, low cost of the chemicals, and the ample supply of lupines, would facilitate the scaling of these laboratory studies to pilot and industrial levels.

Advanced Treatment of Coking Wastewater by Oxidation Process Using Pyrite and Hydrogen Peroxide

2013 ◽  
Vol 726-731 ◽  
pp. 2521-2525
Author(s):  
Zhi Yong Zhang ◽  
De Li Wu
Keyword(s):  
Hydrogen Peroxide ◽  
Oxidation Process ◽  
Low Cost ◽  
Oxygen Demand ◽  
Utilization Efficiency ◽  
Advanced Treatment ◽  
Coking Wastewater ◽  
Second Stage ◽  
Potential Alternative ◽  
High Utilization

Coking wastewater is a kind of recalcitrant wastewater including complicate compositions. Advanced treatment of coking wastewater by Fenton-Like reaction using pyrite as catalyst was investigated in this paper. The results show that the chemical oxygen demand (COD) of coking wastewater decreased significantly by method of coagulation combined with two-stage oxidation reaction. COD of wastewater can decrease from 250mg/l to 45mg/l after treatment, when 2g/L pyrite was used in each stage oxidation and the dosage of hydrogen peroxide (H2O2) is 0.2ml/l for first stage treatment, 0.1ml/l for second stage treatment respectively. The pyrite is effective to promote Fenton-Like reaction with low cost due to high utilization efficiency of H2O2, moreover, catalyst could be easily recovered and reused. The Fenton-Like reaction might be used as a potential alternative to advanced treatment of recalcitrant wastewater.

scholarly journals A Person-to-Person and Person-to-Place COVID-19 Contact Tracing System Based on OGC IndoorGML

2020 ◽  
Vol 10 (1) ◽  
pp. 2 ◽  
Author(s):  
Soroush Ojagh ◽  
Sara Saeedi ◽  
Steve H. L. Liang
Keyword(s):  
Data Model ◽  
Low Cost ◽  
Large Body ◽  
Contact Tracing ◽  
Trajectory Data ◽  
Sequential Order ◽  
Human Contact ◽  
Wide Availability ◽  
Data Points ◽  
The Impact

With the wide availability of low-cost proximity sensors, a large body of research focuses on digital person-to-person contact tracing applications that use proximity sensors. In most contact tracing applications, the impact of SARS-CoV-2 spread through touching contaminated surfaces in enclosed places is overlooked. This study is focused on tracing human contact within indoor places using the open OGC IndoorGML standard. This paper proposes a graph-based data model that considers the semantics of indoor locations, time, and users’ contexts in a hierarchical structure. The functionality of the proposed data model is evaluated for a COVID-19 contact tracing application with scalable system architecture. Indoor trajectory preprocessing is enabled by spatial topology to detect and remove semantically invalid real-world trajectory points. Results show that 91.18% percent of semantically invalid indoor trajectory data points are filtered out. Moreover, indoor trajectory data analysis is innovatively empowered by semantic user contexts (e.g., disinfecting activities) extracted from user profiles. In an enhanced contact tracing scenario, considering the disinfecting activities and sequential order of visiting common places outperformed contact tracing results by filtering out unnecessary potential contacts by 44.98 percent. However, the average execution time of person-to-place contact tracing is increased by 58.3%.

scholarly journals Exploring and Exploiting the Symmetry-Breaking Effect of Cyclodextrins in Mechanomolecules

Symmetry ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 1249 ◽  
Author(s):  
Bruns
Keyword(s):  
Symmetry Breaking ◽  
Chemical Synthesis ◽  
Low Cost ◽  
Molecular Machine ◽  
Advanced Materials ◽  
Breaking Effect ◽  
Planar Chirality ◽  
Conical Shape ◽  
Wide Availability ◽  
Molecular Rings

Cyclodextrins (CDs) are cone-shaped molecular rings that have been widely employed in supramolecular/host–guest chemistry because of their low cost, high biocompatibility, stability, wide availability in multiple sizes, and their promiscuity for binding a range of molecular guests in water. Consequently, CD-based host–guest complexes are often employed as templates for the synthesis of mechanically bonded molecules (mechanomolecules) such as catenanes, rotaxanes, and polyrotaxanes in particular. The conical shape and cyclodirectionality of the CD “bead” gives rise to a symmetry-breaking effect when it is threaded onto a molecular “string”; even symmetrical guests are rendered asymmetric by the presence of an encircling CD host. This review focuses on the stereochemical implications of this symmetry-breaking effect in mechanomolecules, including orientational isomerism, mechanically planar chirality, and topological chirality, as well as how they support applications in regioselective and stereoselective chemical synthesis, the design of molecular machine prototypes, and the development of advanced materials.

Rapid and Green One-Pot Synthesis of Novel 2-(4-Hydroxy-2-oxo-2H-chromen-3-yl)-2-(arylamino)-1H-indene-1,3(2H)-diones

2021 ◽  
Vol 18 ◽  
Author(s):  
Abolfazl Olyaei ◽  
Zahra Ghahremany ◽  
Madieh Sadeghpour
Keyword(s):  
Aromatic Amines ◽  
Low Cost ◽  
Guanidine Hydrochloride ◽  
Reaction Times ◽  
Solvent Free ◽  
One Pot ◽  
Solvent Free Conditions ◽  
The One ◽  
High Yields ◽  
Work Up

: A green and efficient protocol was developed for the one-pot three-component synthesis of novel 2-(4-hydroxy-2-oxo-2H-chromen-3-yl)-2-(arylamino)-1H-indene-1,3(2H)-dione derivatives by the reaction of 4-hydroxycoumarin, ninhydrin and aromatic amines in the presence of guanidine hydrochloride as an organocatalyst under solvent-free conditions. The present approach offers several advantages such as low cost, simple work-up, short reaction times, chromatography-free purification, high yields and greener conditions.

scholarly journals Study of Carbohydrate Hydrolysis From Arracacha Roots (Arracacia Xanthorriza Bancroft) to Produce Fermentable Sugars

2021 ◽  
Vol 41 (2) ◽  
pp. e87365
Author(s):  
Darwin Carranza Saavedra ◽  
Jorge Andrés Alvarado Nuñez ◽  
José Fernando Solanilla Duque ◽  
Claudia Patricia Valenzuela Real
Keyword(s):  
Acetic Acid ◽  
Sulfuric Acid ◽  
Mechanical Damage ◽  
Maximum Level ◽  
Raw Material ◽  
Saturated Steam ◽  
Fermentation Inhibitors ◽  
Carbohydrate Hydrolysis ◽  
Fermentable Carbohydrates ◽  
High Yields

In Colombia, approximately 855 840 tons of arracacha are produced each year. The unsalable postharvest arracacha root (Arracacia xanthorriza Bancroft) is not commercialized, mainly due to mechanical damage or small and misshapen roots. In this work, dry samples were characterized and subjected to two treatments: one using thermal hydrolysis, applying saturated steam at pressures of 0,1034 MPa, 0,2068 MPa, and 0,4137 MPa; and another one using hydrolysis with sulfuric acid in concentrations between 0,252,00 M. Then, the cake resulting from the hydrolysis and filtration process was enzymatically hydrolyzed (Liquozyme SC DS, Novozymes) at 1,5, 5 and 10 KNU/g (pH 6, 80 _C, 2 h). Fermentation inhibitors (acetic acid and furfural) were evaluated in the best pretreatment. The results showed that the treatment with sulfuric acid at 1,00 M (2 h) has high yields in reducing sugars added to enzymatic hydrolysis. The maximum level of fermentable carbohydrates per gram of dry sample (1,04 g/g) was also reached. Regarding the fermentation inhibitors of the reducing sugar, a higher concentration of acetic acid was found with a lower furfural content. Therefore, arracacha discards are a promising raw material to increase the supply of bioethanol.

One-pot synthesis of β-diketimine ligands

2010 ◽  
Vol 88 (10) ◽  
pp. 1040-1045 ◽  
Author(s):  
Ibrahim El-Zoghbi ◽  
Aysha Ased ◽  
Paul O. Oguadinma ◽  
Ekou Tchirioua ◽  
Frank Schaper
Keyword(s):  
Hydrochloric Acid ◽  
Water Use ◽  
Minimum Amount ◽  
One Pot ◽  
One Pot Synthesis ◽  
Toluenesulfonic Acid ◽  
High Yields ◽  
Optimized Conditions

Symmetric N,N′-dialkyl-2-amino-4-imino-pent-2-enes (nacnacRH) can be prepared in high yields in a simple one-pot reaction from acetylacetone and 2 equiv. of amine. Optimized conditions require the azeotropic removal of water, use of a minimum amount of solvent, and of 1 equiv. of acid. Either para-toluenesulfonic acid, hydrochloric acid, or a mixture of both can be employed, with the latter being most advantageous. Symmetric nacnacRH are thus obtained in higher than 95% purity and with 65% yield for R = Me and 80%–95% yields for R = n-Pr, i-Pr, i-Bu, Bn, Cy, and (+)-CH(Me)Ph.

Self-pressurised rapid freezing, a time-efficient and affordable cryo-fixation method for ultrastructural observations on unhatched cyst nematodes

Nematology ◽  
2019 ◽  
Vol 22 (1) ◽  
pp. 103-110
Author(s):  
Myriam Claeys ◽  
Nurul Dwi Handayani ◽  
Vladimir V. Yushin ◽  
Prabowo Lestari ◽  
Antarjo Dikin ◽  
...  
Keyword(s):  
High Pressure ◽  
Fast Rate ◽  
Low Cost ◽  
Heterodera Schachtii ◽  
Fixation Method ◽  
Rapid Freezing ◽  
Chemical Fixation ◽  
High Pressure Freezing ◽  
Cyst Nematodes ◽  
Second Stage

Summary Ultrastructural analysis of the early development of nematodes is hampered by the impermeability of the eggshell to most commonly used fixatives. High-pressure freezing (HPF), a physical cryo-fixation method, facilitates a fast rate of fixation, and by using this method the issue of the uneven delivery of fixative is circumvented. Although HPF results in a superior preservation of the fine structure, the equipment costs impede a wider application of this method. Self-pressurised rapid freezing (SPRF) is an alternative low-cost cryo-fixation method, and its usefulness was evaluated in an ultrastructural study of the eggshell and the cuticle of unhatched second-stage juveniles (J2) of Globodera rostochiensis and Heterodera schachtii. A comparison with conventional (chemical) fixation demonstrates that SPRF fixation results in a remarkably well-preserved ultrastructure of the entire egg including both the eggshell and the cellular details of the unhatched J2. Therefore, SPRF fixation is proposed as an affordable, relatively easy-to-use and time-efficient technique to study the ultrastructure of unhatched J2 and eggs of nematodes.

scholarly journals A Review of Carbon Dots Produced from Biomass Wastes

Nanomaterials ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 2316
Author(s):  
Chao Kang ◽  
Ying Huang ◽  
Hui Yang ◽  
Xiu Fang Yan ◽  
Zeng Ping Chen
Keyword(s):  
Carbon Dots ◽  
Raw Materials ◽  
Low Cost ◽  
Disease Diagnosis ◽  
Good Choice ◽  
Biomass Waste ◽  
Renewable Raw Materials ◽  
Wide Availability ◽  
Low Cytotoxicity ◽  
Synthetic Approaches

The fluorescent carbon dot is a novel type of carbon nanomaterial. In comparison with semiconductor quantum dots and fluorescence organic agents, it possesses significant advantages such as excellent photostability and biocompatibility, low cytotoxicity and easy surface functionalization, which endow it a wide application prospect in fields of bioimaging, chemical sensing, environmental monitoring, disease diagnosis and photocatalysis as well. Biomass waste is a good choice for the production of carbon dots owing to its abundance, wide availability, eco-friendly nature and a source of low cost renewable raw materials such as cellulose, hemicellulose, lignin, carbohydrates and proteins, etc. This paper reviews the main sources of biomass waste, the feasibility and superiority of adopting biomass waste as a carbon source for the synthesis of carbon dots, the synthetic approaches of carbon dots from biomass waste and their applications. The advantages and deficiencies of carbon dots from biomass waste and the major influencing factors on their photoluminescence characteristics are summarized and discussed. The challenges and perspectives in the synthesis of carbon dots from biomass wastes are also briefly outlined.

scholarly journals High-yield hydrogen production from biomass by in vitro metabolic engineering: Mixed sugars coutilization and kinetic modeling

2015 ◽  
Vol 112 (16) ◽  
pp. 4964-4969 ◽  
Author(s):  
Joseph A. Rollin ◽  
Julia Martin del Campo ◽  
Suwan Myung ◽  
Fangfang Sun ◽  
Chun You ◽  
...  
Keyword(s):  
New Technologies ◽  
Plant Biomass ◽  
Low Cost ◽  
Energy Conversion Efficiency ◽  
Green Energy ◽  
High Yield ◽  
Yield Parameters ◽  
Production Of Hydrogen ◽  
Nonlinear Kinetic

The use of hydrogen (H2) as a fuel offers enhanced energy conversion efficiency and tremendous potential to decrease greenhouse gas emissions, but producing it in a distributed, carbon-neutral, low-cost manner requires new technologies. Herein we demonstrate the complete conversion of glucose and xylose from plant biomass to H2 and CO2 based on an in vitro synthetic enzymatic pathway. Glucose and xylose were simultaneously converted to H2 with a yield of two H2 per carbon, the maximum possible yield. Parameters of a nonlinear kinetic model were fitted with experimental data using a genetic algorithm, and a global sensitivity analysis was used to identify the enzymes that have the greatest impact on reaction rate and yield. After optimizing enzyme loadings using this model, volumetric H2 productivity was increased 3-fold to 32 mmol H2⋅L−1⋅h−1. The productivity was further enhanced to 54 mmol H2⋅L−1⋅h−1 by increasing reaction temperature, substrate, and enzyme concentrations—an increase of 67-fold compared with the initial studies using this method. The production of hydrogen from locally produced biomass is a promising means to achieve global green energy production.

scholarly journals Sonography of the iliotibial band: spectrum of findings

2014 ◽  
Vol 47 (1) ◽  
pp. 33-37 ◽  
Author(s):  
Carlos Frederico Arend
Keyword(s):  
Imaging Modality ◽  
Low Cost ◽  
Iliotibial Band ◽  
Band Spectrum ◽  
Correct Identification ◽  
First Line ◽  
Potential Source ◽  
Wide Availability ◽  
Line Imaging ◽  
Clinical Complaint

Iliotibial band lesions constitute a potential source of discomfort and are frequently confounded with other conditions which cause pain on the lateral aspect of the hip, thigh and knee. Ultrasonography is usually regarded as a first-line imaging modality in the assessment of such conditions because of its excellent diagnostic accuracy, low cost and wide availability. The correct identification of the structure involved in the production of symptoms leads to an appropriate management and to a higher probability of resolution of the clinical complaint. The present article is aimed at reviewing the different sonographic presentations of iliotibial band syndromes.

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