scholarly journals Evaluation of Microalgae’s Plastic Biodeterioration Property by a Consortium of Chlorella sp. and Cyanobacteria sp.

2021 ◽  
Vol 77 (3) ◽  
pp. 86-98
Author(s):  
Prakash Bhuyar ◽  
Sathyavathi Sundararaju ◽  
Ho Xuan Feng ◽  
Mohd Hasbi Ab. Rahim ◽  
Sudhakar Muniyasamy ◽  
...  
Keyword(s):  
Polymer Degradation ◽  
Low Density ◽  
Dsc Analysis ◽  
Initial Composition ◽  
Edx Analysis ◽  
Chlorella Sp ◽  
Research Article ◽  
Biological Technique ◽  
Time Required ◽  
Oxygen Ratio

Malaysia is one of the top eight countries that has a drawback of mismanaged plastic waste. This study intended to investigate polymer degradation using the biological technique with the help of microalgae to minimise the time required for biodegradation. This research article aims to identify the collected sample with the most suitable microalgae for the biodegradation of microplastic and to analyse the biodegradation of the polymer by microalgae. The results revealed that the consortium of Chlorella sp. and Cyanobacteria sp. were able to deteriorate low-density polyethene (LDPE sample) through several stages, and this was confirmed by UV-Spec, FESEM, EDX, CHNO, FTIR and DSC analysis. The results obtained revealed that microalgae producing exopolysaccharides (EPS) decreased the carbon and oxygen ratio. According to SEM micrographs, microalga may colonise, agglomerate, and adhere microplastics to its surface, regardless of its fractional size. The EDX analysis showed that the initial composition of carbon was 92.30 ± 1.23 %, while after the incubation, the carbon composition started decreasing from 53.18 % to 39.12 ± 1.08 %. Finally, there was a 37.91 % decrease in carbon weight from elemental analysise

Production with a High Yield of Bacterial Cellulose Nanocrystals by Enzymatic Hydrolysis

2019 ◽  
Vol 19 (03) ◽  
pp. 1950015
Author(s):  
Ricardo Brandes ◽  
Leticia de Souza ◽  
Claudimir Carminatti ◽  
Derce Recouvreux
Keyword(s):  
Enzymatic Hydrolysis ◽  
Bacterial Cellulose ◽  
Cellulose Nanocrystals ◽  
Primary Objective ◽  
High Yield ◽  
Low Density ◽  
Enzymatic Method ◽  
Citrate Buffer ◽  
Cellulose Hydrogel ◽  
Time Required

Bacterial cellulose nanocrystals are highly crystalline structures with nanoscopic scale dimensions that have received increased attention in the nanocomposites area. Its properties, such as large surface area, low density, mechanical strength and ease of modification, are attractive to the preparation many kinds of nanomaterials applied multifunctional in various fields. Besides, the cellulose nanocrystals are from abundant and renewable sources that are biodegradable. An altemative method is to obtain bacterial cellulose nanocrystal by enzymatic hydrolysis because it is, less expensive, it does not use chemicals and it requires much less energy. In this sense, the primary objective of this study was to produce bacterial cellulose using glycerol as a carbon source and isolate nanocrystals from bacterial cellulose using the enzymatic hydrolysis. This study also investigated the yield of nanocrystals depending on the weight of the bacterial cellulose hydrogel, keeping constant some enzymes. The study shows us that the enzymatic method has the best performance when using cellulose hydrogel 2[Formula: see text]g to 40[Formula: see text][Formula: see text]L cellulase enzyme (endoglucanase) and 1[Formula: see text]mL of citrate buffer. Also, it was observed that the yield of nanocrystals decrease with increasing time required for the hydrolysis.

scholarly journals Performance of Pillar and Upright Form Peach Trees Grown in a Central Leader or Multiple Leader Orchard System at Various Planting Densities

HortScience ◽  
2004 ◽  
Vol 39 (4) ◽  
pp. 815A-815
Author(s):  
Stephen Miller* ◽  
Ralph Scorza
Keyword(s):  
Fruit Quality ◽  
Growth Habit ◽  
Growing Season ◽  
Row Spacing ◽  
Low Density ◽  
Four Seasons ◽  
Growth Habits ◽  
Time Required ◽  
Peach Trees ◽  
Plot Design

Peach trees with a pillar (P) (columnar) or upright (UP) growth habit were planted at four in-row spacings (1.5, 2.0, 4.0, and 6.0 m) in 1999 and trained to a central leader or multiple leader system to evaluate their performance in an orchard environment. A standard (S) form peach cultivar (`Harrow Beauty') was included for comparison. In this replicated study using a split-split-split plot design, one-half of the trees were summer pruned (SP) 6 weeks before harvest in each growing season from 2001 to 2003. Growth habit, tree spacing, and SP had a significant effect on tree growth and time necessary for dormant pruning. Growth habit and spacing also affected time required to summer prune. Total pruning time for all growth habits was significantly greater for SP trees compared to non-SP trees. Cumulative yields per tree were greater for UP and S habit trees than P trees over the first four seasons. Per tree yields increased as the in-row spacing increased but were decreased slightly by SP. UP trees consistently produced larger size fruit than P or S trees. Potential yields per ha and pruning times based on projected best tree spacings will be presented. UP form trees provide a good transition for growers going from low-density to high-density peach systems, with significant advantages in yield and fruit quality.

scholarly journals Studies on features, physical, mechanical, tribological properties and applications of Ti-6Al-4V in aerospace industry

2019 ◽  
Vol 5 (7) ◽  
pp. 187 ◽  
Author(s):  
Roopsandeep Bammidi ◽  
K. Siva Prasad ◽  
P. S. Rao
Keyword(s):  
Mechanical Properties ◽  
Tribological Properties ◽  
Elasticity Modulus ◽  
Aerospace Industry ◽  
Physical And Mechanical Properties ◽  
High Strength ◽  
Low Density ◽  
Research Article

<p>This research article gives an overview of the extensive research of Ti-6Al-4V from past few decades helped in studying about the features, properties, characteristics and application of aerospace industries. The final objective of study is to obtain the inherent advantages of Ti-6Al-4V like low elasticity modulus, high strength, low density and more resistant to fatigue and corrosion that leads to rely on the required knowledge for the employment of application which improves all physical and mechanical properties.</p>

scholarly journals Synthesis and characterization of Hydrogels based on Potato Starch/Poly(vinyl Alcohol)/N, N'-Methylenebisacrylamide

2021 ◽  
Author(s):  
DIEGO DAVID PINZON-MORENO ◽  
Eder Clidio Vicuña-Galindo ◽  
José Vulfrano Gonzáles-Fernández ◽  
José Luis Soto-Gonzales ◽  
María Verónica Carranza-Oropeza
Keyword(s):  
Statistical Models ◽  
Vinyl Alcohol ◽  
Potato Starch ◽  
Polymer Degradation ◽  
Poly Vinyl Alcohol ◽  
Dsc Analysis ◽  
General Terms ◽  
Main Components ◽  
Tga And Dsc

Abstract Several hydrogels were synthesized by free-radical polymerization in an aqueous medium based on potato starch (PS), poly(vinyl alcohol) (PVA), and N,N'-Methylenebisacrylamide (MBAm), being possible to study these hydrogels as a function of the proportion of components incorporated. In this way, the products generated from the synthesis were characterized by swelling and deswelling kinetics, the first swelling being verified with Schott and statistical models, allowing to contrast the proximity between the experimental and theoretical behavior. Additionally, spectroscopy (FTIR), morphological (SEM), and thermal (TGA and DSC) analysis allowing to know the intrinsic characteristics of the material, increasing in general terms the knowledge of this type of material. In this context, it was possible to verify the characteristics and effectiveness of the synthesis and crosslinking of the main components. The experimental results obtained show that the synthesized hydrogels present representative first swellings consistent with kinetic and statistical models; however, there are significant changes in the second swelling derived from polymer degradation that occurs during the same swelling/deswelling cycles processes.

scholarly journals MgO-Lignin Dual Phase Filler as an Effective Modifier of Polyethylene Film Properties

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 809 ◽  
Author(s):  
Karol Bula ◽  
Grzegorz Kubicki ◽  
Teofil Jesionowski ◽  
Łukasz Klapiszewski
Keyword(s):  
Lignin Content ◽  
Mechanical Tests ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Screw Extruder ◽  
Hybrid Filler ◽  
Tear Strength ◽  
Twin Screw ◽  
Time Required ◽  
Almost All

Functional magnesium oxide-lignin hybrid materials were obtained via mechanical grinding. Their particle shape and size as well as physicochemical properties were characterized. MgO-lignin materials with biocomponent content (between 20% and 80% amount of total weight of filler) were used as a partially bio-structured modifier of low density polyethylene. The composites with 5% by weight of dual fillers and polyethylene grafted with maleic anhydride were compounded in a twin screw extruder working in co-rotating mode. The prepared blends were cast extruded using a single screw extruder and laboratory cast line. The properties of the obtained films were verified in case of their weldability. The seal strength as well as shear test and tear strength of the welded sheets were examined. The results showed that the shortest equivalent time required to perform correct weld occurred in the system, where the highest amount of lignin was used in hybrid filler MgO-L (1:5 w/w). From mechanical tests of welds, a sharp increase in ultimate seal force was noticed for almost all compositions with lignin, especially where MgO was coupled with a high lignin content. For those composition seal open force raised up to 37.0 N, from the value of 23.6 N, achieved for neat low density polyethylene (LDPE). Tear strength of weld sheets confirmed once more that LDPE composition with MgO-L (1:5 w/w) achieved the highest ultimate force with its value of 71.5 N, and it was ~20.0 N higher than in the case of neat LDPE.

scholarly journals Comparative Morphological Investigation between Natural Photo-Aged of Two Different Low Density Polyethylene Green House Covers

2021 ◽  
Vol 8 (1) ◽  
pp. 1-4
Author(s):  
BabaghayouMeriam Imane ◽  
AbdelHamid Ismail Mourad
Keyword(s):  
Degree Of Crystallinity ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Natural Ageing ◽  
Dsc Analysis ◽  
Polyethylene Films ◽  
Extruded Films ◽  
Different Types ◽  
Degradation Behaviors ◽  
Better Than

This work studies and compares the degradation performance of two different types of blown extruded films of low density polyethylene films used as greenhouse covers. The first one is LDPE (B24/2) supplied by ENIP Skikda and the other one is LDPE (2100 T N00W) supplied by SABIC, Saudi Arabia. Both films are commonly used in Algeria as greenhouse covers. The films were exposed outdoors over a period of 8 months for natural ageing. XRD and DSC analysis were conducted to characterize the thermal properties of the materials and compare between their degradation behaviors. The results revealed that the degradation resistance of LDPE (B24/2) is better than LDPE (2100T N00W) in term of their degree of crystallinity. Keywords: Natural Ageing, LDPE (B24/2); LDPE (2100 T N00W); Degree of Crystallinity, XRD; DSC.

scholarly journals Implementation of Speed-Efficient Key-Scheduling Process of AES for Secure Storage and Transmission of Data

Sensors ◽  
2021 ◽  
Vol 21 (24) ◽  
pp. 8347
Author(s):  
Thanikodi Manoj Kumar ◽  
Kavitha Rani Balmuri ◽  
Adam Marchewka ◽  
Parameshachari Bidare Divakarachari ◽  
Srinivas Konda
Keyword(s):  
Digital Data ◽  
Generation Process ◽  
Gate Arrays ◽  
Secure Storage ◽  
Research Article ◽  
Field Programmable ◽  
Secret Keys ◽  
Programmable Gate Arrays ◽  
Symmetric Key ◽  
Time Required

Nowadays, a large number of digital data are transmitted worldwide using wireless communications. Therefore, data security is a significant task in communication to prevent cybercrimes and avoid information loss. The Advanced Encryption Standard (AES) is a highly efficient secure mechanism that outperforms other symmetric key cryptographic algorithms using message secrecy. However, AES is efficient in terms of software and hardware implementation, and numerous modifications are done in the conventional AES architecture to improve the performance. This research article proposes a significant modification to the AES architecture’s key expansion section to increase the speed of producing subkeys. The fork–join model of key expansion (FJMKE) architecture is developed to improve the speed of the subkey generation process, whereas the hardware resources of AES are minimized by avoiding the frequent computation of secret keys. The AES-FJMKE architecture generates all of the required subkeys in less than half the time required by the conventional architecture. The proposed AES-FJMKE architecture is designed and simulated using the Xilinx ISE 5.1 software. The Field Programmable Gate Arrays (FPGAs) behaviour of the AES-FJMKE architecture is analysed by means of performance count for hardware resources, delay, and operating frequency. The existing AES architectures such as typical AES, AES-PNSG, AES-AT, AES-BE, ISAES, AES-RS, and AES-MPPRM are used to evaluate the efficiency of AES-FJMKE. The AES-FJMKE implemented using Spartan 6 FPGA used fewer slices (i.e., 76) than the AES-RS.

scholarly journals Curing and Characteristics of N,N,N′,N′-Tetraepoxypropyl-4,4′-Diaminodiphenylmethane Epoxy Resin-Based Buoyancy Material

Polymers ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1137 ◽  
Author(s):  
Sizhu Yu ◽  
Xiaodong Li ◽  
Xiaoyan Guo ◽  
Zhiren Li ◽  
Meishuai Zou
Keyword(s):  
Epoxy Resin ◽  
High Strength ◽  
Hollow Glass Microsphere ◽  
Low Density ◽  
Curing Process ◽  
Mass Ratio ◽  
Dsc Analysis ◽  
Scanning Calorimetry ◽  
Saturated Water ◽  
Thermal Analysis Kinetics

Buoyancy material is a type of low-density and high-strength composite material which can provide sufficient buoyancy with deep submersibles. A new buoyancy material with N,N,N′,N′-tetraepoxypropyl-4,4′-diaminodiphenylmethane epoxy resin (AG-80) and m-xylylenediamine (m-XDA) curing agent as matrix and hollow glass microsphere (HGM) as the filler is prepared. The temperature and time of the curing process were determined by the calculations of thermal analysis kinetics (TAK) through differential scanning calorimetry (DSC) analysis. The results show that the better mass ratio of AG-80 with m-XDA is 100/26. Combined TAK calculations and experimental results lead to the following curing process: pre-curing at 75 °C for 2 h, curing at 90 °C for 2 h, and post-curing at 100 °C for 2 h. The bulk density, compressive strength, and saturated water absorption of AG-80 epoxy resin-based buoyancy material were 0.729 g/cm3, 108.78 MPa, and 1.23%, respectively. Moreover, this type of buoyancy material can resist the temperature of 250 °C.

scholarly journals Lossless Immunocytochemistry using Photo-polymerized Hydrogel Thin-films

2020 ◽  
Author(s):  
Jeong Hyun Lee ◽  
Aline T. Santoso ◽  
Emily S. Park ◽  
Kerryn Matthews ◽  
Simon P. Duffy ◽  
...  
Keyword(s):  
Thin Film ◽  
Cell Loss ◽  
Microtiter Plate ◽  
Bottom Surface ◽  
Biological Technique ◽  
Centrifugation Step ◽  
Cell Sample ◽  
Diagnostic Applications ◽  
Rare Cells ◽  
Time Required

AbstractImmunocytochemistry (ICC), or immunofluorescence microscopy, is an essential biological technique for phenotyping cells in both research and diagnostic applications. Standard ICC methods often do not work well when the cell sample contains a small number of cells (<10,000) because of the significant cell loss that occurs during washing, staining, and centrifugation steps. Cell loss is particularly relevant when working with rare cells, such as circulating tumor cells, where such losses could significantly bias experimental outcomes. In order to eliminate cell loss in ICC protocols, we present a method to encapsulate the cell sample in a photo-polymerized hydrogel thin-film. The hydrogel thin-film is permeable to antibodies and other ICC reagents, thereby allowing the use of standard ICC protocols without modification. The cell sample is physically constrained by the hydrogel at the bottom surface of a standard (unmodified) imaging microtiter plate, thereby enabling the acquisition of high-quality micrographs regardless of the properties of the cell sample or staining reagents. Furthermore, while standard ICC requires several centrifugation steps during staining and washing, our hydrogel encapsulation method requires only a single centrifugation step. This property greatly reduces the time required to perform ICC protocols and is more compatible with robotic platforms. In this study, we show that standard ICC and Cytospin protocols are extremely lossy (>70% loss) when the sample contains less than 10,000 cells, while encapsulating the cells using a permeable hydrogel thin-film results in a lossless ICC process.

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