The study of volatile products formation from the self-degradation of l-ascorbic acid in hot compressed water

2022 ◽  
Vol 371 ◽  
pp. 131155
Author(s):  
Liang Feng ◽  
Yan Yang ◽  
Shuang-shuang Liu ◽  
Ding-yun Tan ◽  
Chun Tan ◽  
...  
2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Yan Yang ◽  
Ya Li ◽  
Liang Feng ◽  
Ai-Nong Yu ◽  
Bao-Guo Sun ◽  
...  

AbstractThe non-enzymatic browning (NEB) reaction between l-ascorbic acid (ASA) and glycine (Gly), including the effects of temperature (110–150 °C), time (10–150 min) and pH (4.5, 6.8, 8.0 and 9.5) on the formation of un-colored intermediate products (UIPs), browning products (BPs) and volatile products (VPs), were investigated. The results showed that pH had a remarkable effect on the reaction. The characteristics of zero-order kinetics for the formation of UIPs and BPs were discussed, and the corresponding activation energy (Ea) was also calculated. When the pH was 4.5, the Ea for the formation of UIPs was approximate 53.76 kJ/mol and less than that at other pH values; while the Ea for BPs formation was approximate 94.06 kJ/mol and much higher than that at other pH values. The results suggested that an acidic environment facilitated the generation of UIPs, but did not remarkably promote the formation of BPs. The possible reaction pathway between ASA and Gly was proposed according to the experimental results.


RSC Advances ◽  
2016 ◽  
Vol 6 (52) ◽  
pp. 46388-46393 ◽  
Author(s):  
Binbin Pan ◽  
Wenlei Zhao ◽  
Xiaobo Zhang ◽  
Jinpeng Li ◽  
Jiasheng Xu ◽  
...  

A sandwich-structured nanocomposite of LaNb2O7/CoTMPyP was fabricated via electrostatic interactions between LaNb2O7− nanosheets and cobalt porphyrin cations, and the obtained hybrid film exhibited excellent electrocatalytic activities toward AA.


2011 ◽  
Vol 16 (1) ◽  
pp. 173-178 ◽  
Author(s):  
Ramendra Sundar Dey ◽  
Susmita Gupta ◽  
Rupankar Paira ◽  
Shen-Ming Chen ◽  
C. Retna Raj

1948 ◽  
Vol 20 (1) ◽  
pp. 8-36
Author(s):  
Paavo Roine

Owing to the impossibility of obtaining reliable information on the food consumption of the »self-providers,» only the food rations and nutrition of the ordinary »consumers» are discussed in this paper. The daily amounts of calories, protein, fat, calcium, phosphorus, iron, vitamin A, thiamine, riboflavin, niacin, and ascorbic acid have been calculated on the basis of the rations of bread flour, fats, milk, sugar, and meat. Of the ration-free foodstuffs only potatoes had greater importance in the diets; their contents of different constituents have been taken into consideration in using approximate values of the daily consumption of potatoes. Inadequacy of calories is a common feature in the diets of adults and also of adolescent children. Distinct deficiencies can also be noticed in the amounts of calcium and vitamin A, a slight deficiency in riboflavin. The intake of other constituents discussed can be regarded as being nutritionally adequate, although the amounts of protein and particularly those of niacin have been in many cases rather scanty. The nutrition of children has been remarkably better than that of the adults owing, above all, to the greater share of milk in the children’s dietary. The nutrition situation was the worst in 1942 and very poor again in 1945. In 1946 and later it has been continually improving.


2019 ◽  
Vol 42 ◽  
Author(s):  
Lucio Tonello ◽  
Luca Giacobbi ◽  
Alberto Pettenon ◽  
Alessandro Scuotto ◽  
Massimo Cocchi ◽  
...  

AbstractAutism spectrum disorder (ASD) subjects can present temporary behaviors of acute agitation and aggressiveness, named problem behaviors. They have been shown to be consistent with the self-organized criticality (SOC), a model wherein occasionally occurring “catastrophic events” are necessary in order to maintain a self-organized “critical equilibrium.” The SOC can represent the psychopathology network structures and additionally suggests that they can be considered as self-organized systems.


Author(s):  
M. Kessel ◽  
R. MacColl

The major protein of the blue-green algae is the biliprotein, C-phycocyanin (Amax = 620 nm), which is presumed to exist in the cell in the form of distinct aggregates called phycobilisomes. The self-assembly of C-phycocyanin from monomer to hexamer has been extensively studied, but the proposed next step in the assembly of a phycobilisome, the formation of 19s subunits, is completely unknown. We have used electron microscopy and analytical ultracentrifugation in combination with a method for rapid and gentle extraction of phycocyanin to study its subunit structure and assembly.To establish the existence of phycobilisomes, cells of P. boryanum in the log phase of growth, growing at a light intensity of 200 foot candles, were fixed in 2% glutaraldehyde in 0.1M cacodylate buffer, pH 7.0, for 3 hours at 4°C. The cells were post-fixed in 1% OsO4 in the same buffer overnight. Material was stained for 1 hour in uranyl acetate (1%), dehydrated and embedded in araldite and examined in thin sections.


Author(s):  
Xiaorong Zhu ◽  
Richard McVeigh ◽  
Bijan K. Ghosh

A mutant of Bacillus licheniformis 749/C, NM 105 exhibits some notable properties, e.g., arrest of alkaline phosphatase secretion and overexpression and hypersecretion of RS protein. Although RS is known to be widely distributed in many microbes, it is rarely found, with a few exceptions, in laboratory cultures of microorganisms. RS protein is a structural protein and has the unusual properties to form aggregate. This characteristic may have been responsible for the self assembly of RS into regular tetragonal structures. Another uncommon characteristic of RS is that enhanced synthesis and secretion which occurs when the cells cease to grow. Assembled RS protein with a tetragonal structure is not seen inside cells at any stage of cell growth including cells in the stationary phase of growth. Gel electrophoresis of the culture supernatant shows a very large amount of RS protein in the stationary culture of the B. licheniformis. It seems, Therefore, that the RS protein is cotranslationally secreted and self assembled on the envelope surface.


2020 ◽  
Vol 29 (4) ◽  
pp. 2097-2108
Author(s):  
Robyn L. Croft ◽  
Courtney T. Byrd

Purpose The purpose of this study was to identify levels of self-compassion in adults who do and do not stutter and to determine whether self-compassion predicts the impact of stuttering on quality of life in adults who stutter. Method Participants included 140 adults who do and do not stutter matched for age and gender. All participants completed the Self-Compassion Scale. Adults who stutter also completed the Overall Assessment of the Speaker's Experience of Stuttering. Data were analyzed for self-compassion differences between and within adults who do and do not stutter and to predict self-compassion on quality of life in adults who stutter. Results Adults who do and do not stutter exhibited no significant differences in total self-compassion, regardless of participant gender. A simple linear regression of the total self-compassion score and total Overall Assessment of the Speaker's Experience of Stuttering score showed a significant, negative linear relationship of self-compassion predicting the impact of stuttering on quality of life. Conclusions Data suggest that higher levels of self-kindness, mindfulness, and social connectedness (i.e., self-compassion) are related to reduced negative reactions to stuttering, an increased participation in daily communication situations, and an improved overall quality of life. Future research should replicate current findings and identify moderators of the self-compassion–quality of life relationship.


2012 ◽  
Vol 21 (4) ◽  
pp. 136-143
Author(s):  
Lynn E. Fox

Abstract The self-anchored rating scale (SARS) is a technique that augments collaboration between Augmentative and Alternative Communication (AAC) interventionists, their clients, and their clients' support networks. SARS is a technique used in Solution-Focused Brief Therapy, a branch of systemic family counseling. It has been applied to treating speech and language disorders across the life span, and recent case studies show it has promise for promoting adoption and long-term use of high and low tech AAC. I will describe 2 key principles of solution-focused therapy and present 7 steps in the SARS process that illustrate how clinicians can use the SARS to involve a person with aphasia and his or her family in all aspects of the therapeutic process. I will use a case study to illustrate the SARS process and present outcomes for one individual living with aphasia.


2017 ◽  
Vol 2 (9) ◽  
pp. 3-9 ◽  
Author(s):  
Kristina M. Blaiser ◽  
Mary Ellen Nevins

Interprofessional collaboration is essential to maximize outcomes of young children who are Deaf or Hard-of-Hearing (DHH). Speech-language pathologists, audiologists, educators, developmental therapists, and parents need to work together to ensure the child's hearing technology is fit appropriately to maximize performance in the various communication settings the child encounters. However, although interprofessional collaboration is a key concept in communication sciences and disorders, there is often a disconnect between what is regarded as best professional practice and the self-work needed to put true collaboration into practice. This paper offers practical tools, processes, and suggestions for service providers related to the self-awareness that is often required (yet seldom acknowledged) to create interprofessional teams with the dispositions and behaviors that enhance patient/client care.


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