Study of physical and chemical modifications induced by 50MeV Li3+ ion beam in polymers

: Kojic acid is an organic acid that is commonly used in the pharmaceutical and cosmetic industries. This acid compound is a secondary metabolite produced by various microorganisms, one of which is Aspergillus oryzae. Typically, improving the strain can enhance kojic acid production. A mutation is one of the tools to perform strain improvement because the change in kojic acid-producing genes effectively increases kojic acid yield. Random mutagenesis is a classic approach for inducing and producing mutants with random mutations. The mutagenesis can be generated by the individual physical and chemical mutagen, combined physical and chemical mutagens, or initiate by protoplast preparation. Aspergillus strains that are exposed to physical mutagens (e.g., UV) or chemical mutagens (e.g., N-methyl-N-nitro-N-nitrosoguanidine (NTG)) showed their abilities in increasing kojic acid production. Several new mutation methods, such as Ion Beam Implantation and Atmospheric and room temperature plasma (ARTP), also showed good responses in enhancing the production of biological products such as kojic acid. This review compared different random mutagenesis methods of Aspergillus strain with various mutagen types to provide better insight for researchers in choosing the most suitable method to increase kojic acid production.

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Modified Starches as Direct Compression Excipients - Effect of Physical and Chemical Modifications on Tablet Properties: A Review

Starch - Stärke ◽

10.1002/star.201800040 ◽

2018 ◽

Vol 71 (1-2) ◽

pp. 1800040 ◽

Cited By ~ 9

Author(s):

Mariam V. Lawal

Keyword(s):

Direct Compression ◽

Chemical Modifications ◽

Modified Starches ◽

Tablet Properties ◽

Physical And Chemical

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In vivo evaluation in man by two noninvasive methods of the stratum corneum barrier function after physical and chemical modifications

International Journal of Cosmetic Science ◽

10.1111/j.1467-2494.1991.tb00031.x ◽

1991 ◽

Vol 13 (6) ◽

pp. 293-302 ◽

Cited By ~ 25

Author(s):

F. KOMPAORE ◽

Ch. DUPONT ◽

J.P. MARTY

Keyword(s):

Stratum Corneum ◽

Barrier Function ◽

Chemical Modifications ◽

Noninvasive Methods ◽

In Vivo Evaluation ◽

Physical And Chemical

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Physical and Chemical Effects of Focused Ga-Ion Beam on GaAs (100)

MRS Proceedings ◽

10.1557/proc-268-301 ◽

1992 ◽

Vol 268 ◽

Cited By ~ 1

Author(s):

Wei Chen ◽

P. Chen ◽

R. Viswanathan ◽

A. Madhukar ◽

Jun Chen ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Ion Beam ◽

Droplet Formation ◽

Chemical Effects ◽

Milled Surface ◽

Auger Microscopy ◽

Physical And Chemical ◽

Instantaneous Energy ◽

Scanning Electron

ABSTRACTGa droplet formation on GaAs(100) substrates milled by focused Ga ion beam is studied using scanning electron microscopy and scanning Auger microscopy. It is found that Ga droplet formation requires a threshold Ga+ dose of ∽ 1016/cm 2 and is closely correlated to the formation of Ga overlayer at the milled surface and the increase in Ga concentration by ∽ 32% in the subsurface region. The Ga droplet evolution appears to be driven by the instantaneous energy deposited continuously by the ions.

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CYCLIC BUTYLENE TEREPHTHALATE AND PROMISING FIELD OF APPLICATION

IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA ◽

10.6060/tcct.2017607.5558 ◽

2017 ◽

Vol 60 (7) ◽

pp. 4

Author(s):

Nikolay A. Chukov ◽

Muslim A. Mikitaev ◽

Mukhamed Kh. Ligidov ◽

Musa T. Bashorov ◽

Vladimir N. Shogenov ◽

...

Keyword(s):

Carbon Fibers ◽

Atmospheric Pressure ◽

Ring Opening ◽

Glass Fibers ◽

Ring Opening Polymerization ◽

Chemical Modifications ◽

Butylene Terephthalate ◽

Cyclic Butylene Terephthalate ◽

Physical And Chemical ◽

Structure Properties

Due to its unique characteristics, cyclic butylene terephthalate is used in novel developments of chemical industry. This article represents the review of the latest achievements in the field of processing, structure, properties of cyclic butylene terephthalate, its physical and chemical modifications as well as composites and nanocomposites based on it. In recent years, cyclic butylene terephthalate oligomers have drawn the attention of scientists. The oligomers can be acquired through the chemical reaction of cyclo-depolymerization and used as materials for ring-opening polymerization reactions. This method of polymerization has a variety of advantages compared to a standard method of synthesis polyesters. One of the main advantages of this method includes the capability to make polymerization reactions at standard atmospheric pressure, low required temperature, no side effects and obtaining a completely finished product as an outcome. The unique qualities of cyclic butylene terephthalate make it a promising material to be used as matrix for a variety of nano- and microcomposites and super concentrate. This study analyzes some of the examples of applying CBT as a super concentrate for creating materials like carbon nanotubes, laminated silicates, carbon fibers and glass fibers. In the majority of studies, the addition of nano-sized fillers into CBT leads to amplification of mechanical properties. In the cases of usage as fillers for carbon fibers and glass fibers, the possibility of replacing thermosetting resins with CBT is currently being researched. It could possibly lead to increase in manufacturability of carbon fibers and fiberglass and increase its possible area of application. Cyclic butylene terephthalate can also be used as a viscosity modifier for synthetic rubbers. In this case it can be both plasticizer and enhancing agent.For citation:Chukov N.A., Mikitaev M.A., Ligidov M.Kh., Bashorov M.T., Shogenov V.N., Pakhomov S.I. Cyclic butylene terephthalate and promising field of application. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 7. P. 4-13.

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Karakterisasi sifat fisiko kimia pati bengkuang (Pachirrhyzus erosus) dan pati ganyong (Canna edulis Kerr) modifikasi [Characteristization on physico-chemical properties of modified canna (Canna edulis Kerr.) and jicama (Pachirrhyzus erosus) starches]

Jurnal Teknologi & Industri Hasil Pertanian ◽

10.23960/jtihp.v26i1.25-36 ◽

2021 ◽

Vol 26 (1) ◽

pp. 25

Author(s):

Sri Haryani Anwar ◽

Yeni Chandra Dewi ◽

Novi Safriani

Keyword(s):

Chemical Properties ◽

National Standard ◽

Chemical Modifications ◽

Solubility In Water ◽

Food Industries ◽

Swelling Power ◽

Physico Chemical ◽

Moisture Treatment ◽

Modified Starches ◽

Physical And Chemical

Modification of native starch is needed mainly to increase its solubility in water thus broaden its application in food industries. On the other hand, modification of canna and jicama starches have rarely been applied. Physical and chemical modifications of starches are conducted to modify starch characteristics. The research aimed to investigate the physico-chemical properties of canna and jicama starches that had been modified chemically and physically. Chemical modifications which were conducted included modification via substitution with Octenyl Succinate Anhydride (OSA) and hydrolysis using hydrochloric acid (HCl), while physical modification was conducted via the Heat Moisture Treatment (HMT). The starch physico-chemical characteristics evaluated were degree of acid (DA), swelling power, degree of substitution (DS), moisture, ash, fat, and fiber contents. The analysis results showed that moisture, ash, fat, and fiber contents of native canna and jicama starches were not significantly different from those of modified ones. The result also revealed that the type of starches and modification methods increased the swelling power significantly (P≤0,05). The DS of modified canna dan jicama starches were 0.0246% and 0.0176%, respectively. While the DA of modified canna and jicama starches were 0.14% and 0.18%, respectively. This DA values of modified starches by HCL hydrolysis had meet the Indonesian National Standard (SNI 01-2593-1992) which is maximum of 5% for food application.Keywords: canna starch, jicama starch, HMT modification, modified starch, OSA modification

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Chemical modifications of castor oil: A review

Science Progress ◽

10.1177/0036850419859118 ◽

2019 ◽

Vol 102 (3) ◽

pp. 199-217

Author(s):

Ntsako Portia Chauke ◽

Hembe Elie Mukaya ◽

Diakanua Bavon Nkazi

Keyword(s):

Renewable Resources ◽

Castor Oil ◽

Fossil Fuels ◽

Chemical Properties ◽

Environmental Concerns ◽

Chemical Modifications ◽

Plant Oil ◽

Natural Oils ◽

Physical And Chemical ◽

And Chemical Properties

The necessity of using petrochemicals for the development of polymers has been deteriorating because of the depletion in fossil fuels and environmental concerns such as the effect of greenhouse gases, global warming, and increasing population. Research has shown a shift from petroleum-based fuels to plant oil–based fuels in order to shift to renewable resources. Natural oils such as castor oil have shown competitive physical and chemical properties as compared to fossil fuels. The use of natural oils has gained a lot of research interest due to the fact that they are renewable, affordable, and environmentally friendly. Bio-oils are versatile because they have various derivatives and can be used in different grades based on the application in various industries such as agriculture, food, paper, and electronics. Bio-binders have been considered as the most promising materials for the different applications. In this review, the processes of chemical modifications of castor oil are discussed.

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