scholarly journals Heterochiral nucleic acid circuits

2019 ◽  
Vol 3 (5) ◽  
pp. 501-506 ◽  
Author(s):  
Adam M. Kabza ◽  
Brian E. Young ◽  
Nandini Kundu ◽  
Jonathan T. Sczepanski
Keyword(s):  
Synthetic Biology ◽  
Nucleic Acids ◽  
Chemical Properties ◽  
Sequence Information ◽  
Physical And Chemical Properties ◽  
Strand Displacement ◽  
Potential Applications ◽  
The Stability ◽  
Physical And Chemical ◽  
And Chemical Properties

The programmability of DNA/RNA-based molecular circuits provides numerous opportunities in the field of synthetic biology. However, the stability of nucleic acids remains a major concern when performing complex computations in biological environments. Our solution to this problem is l-(deoxy)ribose nucleic acids (l-DNA/RNA), which are mirror images (i.e. enantiomers) of natural d-nucleotides. l-oligonucleotides have the same physical and chemical properties as their natural counterparts, yet they are completely invisible to the stereospecific environment of biology. We recently reported a novel strand-displacement methodology for transferring sequence information between oligonucleotide enantiomers (which are incapable of base pairing with each other), enabling bio-orthogonal l-DNA/RNA circuits to be easily interfaced with living systems. In this perspective, we summarize these so-called ‘heterochiral’ circuits, provide a viewpoint on their potential applications in synthetic biology, and discuss key problems that must be solved before achieving the ultimate goal of the engineering complex and reliable functionality.

Synthesis and Kinetic Investigations for the Isomerization Process of 2–Hydroxy Chalcone Derivatives

2019 ◽  
Vol 41 (6) ◽  
pp. 1046-1046
Author(s):  
Omar A Shareef Omar A Shareef ◽  
Said A Said and Ali Y Abdulrazaq Said A Said and Ali Y Abdulrazaq
Keyword(s):  
Biological Activities ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Pseudo First Order Reaction ◽  
First Order ◽  
Steric Factors ◽  
Kinetic Investigations ◽  
The Stability ◽  
Physical And Chemical ◽  
And Chemical Properties

The wide biological activities of flavanones are mainly depends on their physical and chemical properties, thus a number of substituted 2-Hydroxy chalcones have been synthesized, and their isomerization to their corresponding flavanones was studied. In order to determine the rate constant, kinetic experiments were performed using HPLC technique in (9:1) (CH3CN:H2O) medium at different temperature (298-318) K. The obtained results were interpreted by four steps mechanism, which considered the existence of phenoxide ion as the key intermediate. This study performed with a pseudo first order ( reaction in which the rate for the studied compounds follow the sequence 5 andgt; 2 andgt; 1 andgt; 4 andgt; 3, the activation energy have the same sequence for these compounds .The effect of substituents on the rate showed that electronic and steric factors play reasonable role on the stability of the product .

The Establishment of the 3rd National Reference Standard for Tachypleus Tridentatus Lysate

2017 ◽  
Vol 6 (3) ◽  
pp. 50
Author(s):  
Tong Cai ◽  
Guolai Zhang ◽  
Yusheng Pei ◽  
Hua Gao
Keyword(s):  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Reference Standard ◽  
Tachypleus Tridentatus ◽  
National Reference ◽  
The Stability ◽  
Physical And Chemical ◽  
And Chemical Properties

<p><strong>Objective</strong>  To establish the 3rd national reference standard for Tachypleus Tridentatus Lysate Reagent. <strong>Method</strong> <strong>and Results</strong>  The candidates of reference standard were studied for the physical and chemical properties, and the stability. To determined its sensitivity by collaboration calibration. <strong>Conclusions</strong>  The sensitivity of the 3rd national reference standard for TAL is 0.06EU / ml, lot number is 150603-201003.</p>

scholarly journals An emerging Janus MoSeTe material for potential applications in optoelectronic devices

2019 ◽  
Vol 7 (39) ◽  
pp. 12312-12320 ◽  
Author(s):  
Xiaoyong Yang ◽  
Deobrat Singh ◽  
Zhitong Xu ◽  
Ziwei Wang ◽  
Rajeev Ahuja
Keyword(s):  
First Principles ◽  
Transition Metal Dichalcogenides ◽  
Chemical Properties ◽  
Detailed Comparison ◽  
Physical And Chemical Properties ◽  
First Principles Calculations ◽  
Potential Applications ◽  
Metal Dichalcogenides ◽  
Physical And Chemical ◽  
And Chemical Properties

Motivated by the extraordinary physical and chemical properties of Janus transition-metal dichalcogenides (TMDs) due to the change of the crystal field originating from their asymmetry structures, the electronic and optical properties of the MoSeTe monolayer in 2H and 1T phases are systematically studied by first-principles calculations, and a detailed comparison with the parental MoSe2 and MoTe2 monolayer is made.

scholarly journals Synthesis and applications of carbon nanofibers: a review

2020 ◽  
Vol 36 (4) ◽  
pp. 493-511 ◽  
Author(s):  
Juan C. Ruiz-Cornejo ◽  
David Sebastián ◽  
Maria J. Lázaro
Keyword(s):  
Fuel Cell ◽  
Carbon Nanofibers ◽  
Storage Systems ◽  
Chemical Properties ◽  
Catalytic Decomposition ◽  
Physical And Chemical Properties ◽  
Potential Applications ◽  
Catalytic Supports ◽  
Physical And Chemical ◽  
And Chemical Properties

AbstractCarbon nanofibers (CNFs) have shown great potential in multiple applications. Their versatility is derived from the possibility of tuning their physical and chemical properties. CNFs can be synthesized using two main methods: the catalytic decomposition of carbon precursors or the electrospinning and carbonization of polymers. The most appropriate method relies on the desired characteristics of the CNFs. Some of their applications include the synthesis of catalysts and catalytic supports, as electrodes for fuel cell devices, in hydrogen storage systems, and in functional nanocomposites. In this review, recent advances in the synthesis and potential applications of CNFs are examined.

Salting-out and salting-in experiments with lignosulfonates (LSs)

Holzforschung ◽  
2013 ◽  
Vol 67 (5) ◽  
pp. 549-557 ◽  
Author(s):  
Bernt O. Myrvold
Keyword(s):  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Salting Out ◽  
Practical Applications ◽  
Common Ion ◽  
The Common ◽  
Common Ion Effect ◽  
The Stability ◽  
Physical And Chemical ◽  
And Chemical Properties

Abstract The solubility of lignosulfonates (LSs) in water is strongly dependent on other ions present in the water phase. The differences in the solubility might strongly influence the measurements of the physical and chemical properties of the LS molecules. A reduced solubility of the LS might also affect its utility in many practical applications. The understanding of the interaction between LSs and various salts is important for both practical and theoretical reasons. Therefore, the effect of salt concentrations on the LS has been investigated for 41 different salts with 14 different cations and 16 different anions. The observations cannot be explained by the common ion effect or the screening effects. On the contrary, it was found that the stability of LS solutions follows the Hofmeister series, with the exception of those ions that will chemically interact with the LS molecule. Moreover, the positions of phosphate (HPO42-) and sulfate (SO42-) ions were reversed.

scholarly journals Agrochemical properties of soils of land plots of the Park «Tikhiy Otdykh» of Saint Petersburg

2021 ◽  
pp. 102-117
Author(s):  
В.Ф. Ковязин ◽  
П.М. Демидова ◽  
Е.А. Иванова
Keyword(s):  
Geographical Information Systems ◽  
Current Problem ◽  
Chemical Properties ◽  
Geographical Information ◽  
Physical And Chemical Properties ◽  
Saint Petersburg ◽  
Agrochemical Properties ◽  
The Stability ◽  
Physical And Chemical ◽  
And Chemical Properties

Статья посвящена актуальной проблеме формирования устойчивости парковых насаждений, произрастающих на почвах с различными физико-химическими свойствами. Приведены характерные агрохимические свойства почв парка «Тихий отдых» Санкт-Петербурга. По каждому агрохимическому показателю почвы разработаны с использованием современных географических информационных систем (ГИС) тематические карты в масштабе 1:10000 с применением программного комплекса AutoCAD. С использованием данного комплекса рассчитаны площади земельных угодий, имеющих различные физико-химические свойства почвы. В настоящее время данная проблема городских садово-парковых объектов мало изучена и требует дальнейших исследований, именно этой тематике и посвящены изложенные в статье результаты исследований. The article is devoted to the current problem of forming the stability of Park stands growing on soils with different physical and chemical properties. The characteristic agrochemical properties of the soils of the Park «Tikhiy Otdykh» of St. Petersburg are given. For each agrochemical indicator of the soil, thematic maps were developed using modern geographical information systems (GIS) at a scale of 1:10000 using the AutoCAD software package. Using this complex, the areas of land with different physical and chemical properties of the soil are calculated. At present, this problem of urban garden and Park objects is poorly studied and requires further research. These results presented in the article are devoted to this topic.

Grafting of Hydroxy-Terminated Polybutadiene with 2-Mercaptoethanol

2002 ◽  
Vol 67 (12) ◽  
pp. 1899-1910 ◽  
Author(s):  
Alexander Pleska ◽  
Iva Klichová ◽  
Jindřich Pytela
Keyword(s):  
Chemical Properties ◽  
Radical Addition ◽  
Physical And Chemical Properties ◽  
Scanning Calorimetry ◽  
Polyurethane Elastomers ◽  
Volatile Solvents ◽  
Hydrolytic Resistance ◽  
The Stability ◽  
Physical And Chemical ◽  
And Chemical Properties

A method for functionalization of hydroxy-terminated polybutadiene with 2-sulfanylethan-1-ol (2-mercaptoethanol) leading to a controlled increase in the OH functionality of the polymer was developed. The polybutadiene used contained about 65% of unsaturation in the form of 1,2-vinyl groups. The reaction was carried out without using volatile solvents. The radical addition of 2-sulfanylethan-1-ol on the polymer proceeded quantitatively and the products were free of the mercaptan odour. A series of functionalized polybutadienes were synthesized and characterized by their physical and chemical properties. The differential scanning calorimetry and thermogravimetric analysis measurements revealed that the functionalization improves the stability of the polybutadiene to thermooxidation. The obtained polymers were used for the preparation of polyurethane elastomers. The effect of the increased functionality of the polybutadiene on mechanical properties, thermal behavior and hydrolytic resistance of the elastomers was assessed.

scholarly journals Dyeing of Innovative Bicomponent Filament Fabrics (PET/PTT) by Disperse Dyestuffs: Characterization and Optimization Process

Processes ◽  
2020 ◽  
Vol 8 (5) ◽  
pp. 501 ◽  
Author(s):  
Marwa Souissi ◽  
Ramzi Khiari ◽  
Wafa Haddar ◽  
Mounir Zaag ◽  
Nizar Meksi ◽  
...  
Keyword(s):  
Elastic Recovery ◽  
Chemical Properties ◽  
Disperse Dyes ◽  
Physical And Chemical Properties ◽  
Color Strength ◽  
Scanning Calorimetry ◽  
Dyeing Process ◽  
The Stability ◽  
Physical And Chemical ◽  
And Chemical Properties

PET/PTT bicomponent filaments yarn is produced by two polymers: the polyethylene terephthalate (PET) and the polytrimethylene terephtalate (PTT) extruded side by side. This yarn is known for its high mechanical properties in particular elasticity and elastic recovery. However, differences between physical and chemical properties of the two components make the dyeing step of this yarn complicated. The aim of this work is the development of a dyeing process for bicomponent filaments without altering their physical and chemical properties. Different techniques such as SEM, FTIR, and differential scanning calorimetry (DSC) were used to characterize the studied yarn. For dyeing, three different disperse dyes CI Disperse Red 167.1, CI Disperse Yellow 211, and CI Disperse Red 60 with different energy classes were studied. The influence of dyeing conditions in particular dyeing temperature, pH of dye bath, dyeing time, and carrier concentration in the dye bath was evaluated. Responses analyzed are color strength (K/S), colorimetric coordinates and color fastness of samples dyed with studied dyes. In addition, the stability of elasticity and elastic recovery of bicomponent filament fabrics after the dyeing process has been also verified and proved.

REACTIONS OF ORGANOTIN COMPOUNDS: I. THE STABILITY OF DIMETHYLTIN DIHYDRIDE, AND ADDITIONS TO SOME FLUORO-OLEFINS

1963 ◽  
Vol 41 (11) ◽  
pp. 2889-2897 ◽  
Author(s):  
H. C. Clark ◽  
Sharon G. Furnival ◽  
J. T. Kwon
Keyword(s):  
Ultraviolet Light ◽  
Ultraviolet Irradiation ◽  
Chemical Properties ◽  
Addition Product ◽  
Organotin Compounds ◽  
Physical And Chemical Properties ◽  
Decomposition Products ◽  
The Stability ◽  
Physical And Chemical ◽  
And Chemical Properties

The effect of heat and ultraviolet irradiation on dimethyltin dihydride is reported. At 120°, the major decomposition products are (CH3)3SnH, Sn, and H2, with a small amount of (CH3)6Sn2. At 130° under ultraviolet light, decomposition is much more rapid giving (CH3)3SnH, Sn, and H2, and an appreciable quantity of (CH3) 4Sn. If the dihydride is maintained under these conditions for a longer period (40 hours), (CH3)6Sn2 is formed in place of (CH3)3SnH, and other products are (CH3)4Sn, Sn, and H2. Negligible decomposition occurs at 25° even under irradiation.The ready addition of C2F4 to (CH3)2SnH2 gives the first reported mono-addition product of an organotin dihydride, (CH3)2SnH(C2F4H), as well as (CH3)2Sn(C2F4H)2. Physical and chemical properties of these compounds are described. The additions of (CH3)2SnH2 to CF2CFH, CF2CH2, and CF2CFBr are reported and the results interpreted in terms of the formation of unstable mono-addition products, (CH3)2SnH(C2FnXmHp). Surprisingly, these species decompose through the exchange of halogen and hydrogen between (CH3)2SnH2 and the olefin. Thus, usual products from the reaction of (CH3)2SnH2 with CF2CFBr are (CH3)2SnBr2 and CF2CFH, with some (CH3)3SnBr.

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