scholarly journals Synthesis and Properties of Cyclopentyl Cardo-Type Polyimides Based on Dicyclopentadiene

Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2029 ◽  
Author(s):  
Shih-Chieh Yeh ◽  
Jen-Yu Lee ◽  
Chung-Ta Hsieh ◽  
Ya-Chin Huang ◽  
Kuan-Syun Wang ◽  
...  
Keyword(s):  
Nucleophilic Substitution ◽  
Tensile Properties ◽  
Gas Separation ◽  
Organic Solvents ◽  
The Other ◽  
Hydrogenation Process ◽  
Large Elongation ◽  
Structure Properties

A crucial polymer intermediate, 4-[1-(4-hydroxyphenyl)cyclopentyl]-phenol (bisphenol CP), was developed from dicyclopentadiene (DCPD), a key byproduct of the C5 fraction in petrochemicals. On the basis of bisphenol CP, a diamine, 4,4′-((cyclopentane-1,1-diylbis(4,1-phenylene))bis(oxy))-dianiline (cyclopentyl diamine; CPDA) was subsequently obtained through a nucleophilic substitution of bisphenol CP, followed by the hydrogenation process. By using the CPDA diamine, a series of polyimides with cyclopentyl (cardo) units on the backbone were prepared along with a reference polyimide (API-6F) based on 4,4′-(4,4′-(propane-2,2-diyl)bis(4,1-phenylene))bis(oxy)dianiline (BPAA), and 4,4′-(hexafluoroisopropylidene)-diphthalic anhydride (6FDA) for the exploration of structure-properties relationship. Thanks to the presence of cyclopentyl units, this type of cardo polyimides exhibited comparable tensile properties, especially a large elongation (25.4%). It is also worth noting that CPI-6F exhibited better solubility in organic solvents, such as NMP, DMAc, THF, and chloroform, than the other PIs. Gas separation properties were also evaluated for these cardo-type polyimides.

Effect of Catfish Bone Paste on the Properties of Steamed Bread

2014 ◽  
Vol 881-883 ◽  
pp. 757-760
Author(s):  
Xiao Qing Ren ◽  
Li Zhen Ma ◽  
Xin Yi He
Keyword(s):  
Weight Loss ◽  
Specific Volume ◽  
Cell Structure ◽  
The Other ◽  
Gas Cell ◽  
A Value ◽  
Crumb Structure ◽  
Steamed Bread ◽  
Different Levels ◽  
Structure Properties

The objective of this study was to examine the effect of different levels of catfish bone paste to flour on the physicochemical, textural and crumb structure properties of steamed bread. Six different levels (0, 1, 3, 5, 7,10 %) of catfish bone paste to flour were used in the formulation of the steamed bread. The results showed that the weight loss and TTA of steamed bread decreased with an increase in the levels of the catfish bone paste. On the other hand, the pH increased with an increase in the levels of the catfish bone paste. The specific volume, hardness, chewiness and gas cell structure in the crumb of steamed bread with catfish bone paste at 5% supplementation level were better. Thus, a value of 5% catfish bone paste was considered a better level for incorporation into the steamed bread.

Synthesis of Steroid–Porphyrin Conjugates from Oestradiol, Oestrone, and Lithocholic Acid

2014 ◽  
Vol 67 (11) ◽  
pp. 1632 ◽  
Author(s):  
Fargol Taba ◽  
Tze Han Sum ◽  
Paul J. Sintic ◽  
Ann H. Lundmark ◽  
Maxwell J. Crossley
Keyword(s):  
Nucleophilic Substitution ◽  
Substitution Reaction ◽  
Lithocholic Acid ◽  
The Other ◽  
Nucleophilic Substitution Reaction ◽  
Porphyrin Synthesis ◽  
Synthesis Reactions ◽  
Steroid Conjugates ◽  
The Way

The synthesis of porphyrin–steroid conjugates is examined using the natural steroids oestradiol, oestrone, and lithocholic acid as precursors. Two strategies differing in the timing of formation of the steroid–porphyrin linkage leading to four different construction motifs are explored. Two approaches are based on a strategy of introduction of steroidal components in the porphyrin-forming reaction involving condensation of steroidal-alkylaldehydes and pyrrole to give 5,10,15,20-tetrakis(steroidal-alkyl)porphyrins and differ in the way in which the required aldehyde is introduced to the steroidal component. In the other strategy, a steroidal component is introduced by post-porphyrin synthesis reactions and here also two approaches were explored, one involving nucleophilic substitution and the other esterification. Of the four approaches investigated, the most efficient and most versatile one attaches the steroidal components late in the sequence to a 5,10,15,20-tetra(ω-haloalkyl)porphyrin by a nucleophilic substitution reaction. In this way, a 5,10,15,20-tetrakis[oestrone-linked-heptyl)porphyrin was obtained in 47 % yield.

Effect of Weld Side Combination on Mechanical Properties of Double Sided Friction Stir Welded 5083 Aluminum Alloy

2014 ◽  
Vol 699 ◽  
pp. 169-174
Author(s):  
Achmad Zubaydi ◽  
Nurul Muhayat ◽  
Budie Santosa ◽  
Dony Setyawan
Keyword(s):  
Mechanical Properties ◽  
Aluminum Alloy ◽  
Tensile Properties ◽  
Welded Joints ◽  
Welding Process ◽  
The Other ◽  
Butt Welds ◽  
Friction Stir ◽  
Other Hand ◽  
5083 Aluminum Alloy

Double sided friction stir butt welds on 6 mm thick of 5083 aluminum alloy were produced. Two variants of the weld side combination, different weld side (DS) and same weld side (SS), have been made to investigate the effect of the weld side on mechanical properties.The SS is a double sided welding process that produces advancing side in one plate and retreating side in the other one. On the other hand, the DS is a double sided welding process that causes advancing side and retreating side in each plate. Tensile properties of the joints were evaluated and correlated with macrostructure and hardness. The weld side influenced the macrostructure and mechanical properties of welded joints. The different weld side (DS) had better mechanical properties than the same weld side (SS).

Co-extraction of phosphoric and tetrachloroferric acids

1968 ◽  
Vol 46 (4) ◽  
pp. 662-663 ◽  
Author(s):  
Robert H. McCorkell ◽  
John W. Irvine Jr.
Keyword(s):  
Phosphoric Acid ◽  
Aqueous Solutions ◽  
Organic Solvents ◽  
Strong Acid ◽  
Ionic Species ◽  
The Other ◽  
Solvent Properties

The presence of an extracting strong acid greatly enhances the extraction of phosphoric acid from aqueous solutions into organic solvents, but no type of compound forms between the phosphoric acid and the other extracted species. Only the alteration of the solvent properties when an ionic species and water are added to it can account for the increase in [Formula: see text]

Full Scale Reeling Simulation Tests of Girth Welded X60 HFW Linepipe

2016 ◽  
Author(s):  
Teruki Sadasue ◽  
Satoshi Igi ◽  
Kenji Oi ◽  
Satoru Yabumoto
Keyword(s):  
Brittle Fracture ◽  
Plastic Strain ◽  
Yield Strength ◽  
Tensile Properties ◽  
Local Buckling ◽  
Full Scale ◽  
The Other ◽  
Simulation Test ◽  
Other Hand ◽  
Girth Welds

The reel-lay method is a fast and cost efficient installation process for offshore rigid steel pipelines. Pipelines installed by the reel-lay method are plastically deformed due to reeling, unreeling, aligning and straightening during pipeline installation. Therefore, local buckling is one of the major concerns from a view point of integrity in linepipes, especially around girth welds where strength mismatching arises due to adjacent pipes with different yield strength. One the other hand, the change in mechanical properties of linepipes during reel-lay, including coating process (e.g. 250°C) and long time exposure (e.g. 250°C aging) after installation is also important in order to guarantee safety of linepipes. Furthermore fracture toughness at girth weld Coarse-grain HAZ (CGHAZ) after reeling and aging should be clear to prevent brittle fracture of offshore linepipes in service. In this study, full scale reeling simulation tests of girth welded X60 HFW (High Frequency electric resistance Welded) linepipes with OD; 323.9mm and WT;15.9mm after full body heat treatment (coating simulation) were conducted at 5cycles and 2cycles reeling and straightening situations when yield strength mismatches are present between adjacent pipes around girth welds. Localized strain concentration was observed near girth welds by strength mismatching of adjacent pipes. DNV ovality increased with increasing reeling and straightening cycles, however the ovality did not exceed 10%, which was a criterion value for local buckling, after 5cycles reeling simulation test. The change ratio of wall thickness after full scale reeling simulation tests were about ±2% (within DNV-OS-F101 tolerance) regardless of circumferential and longitudinal direction of pipes. Longitudinal tensile properties could be characterized by axial last introduced plastic strain. That is, in the positive number of last introduced plastic strain, YS and Y/T increased, while uEl decreased by work hardening effect. On the other hand YS and Y/T decreased, while uEl increased at the negative number of last introduced plastic strain by Bauschinger effect. Circumferential tensile properties could be also characterized by axial last introduced plastic strain. Yield strength and Y/T slightly increased while uniform elongation slightly decreased by aging at longitudinal and circumferential direction. Tensile properties did not change irrespective of the number of cycles of reeling simulation tests. After 5cycles reeling simulation test and aging, girth welded CGHAZ CTOD values were over 0.4mm at −20°C and Charpy absorbed energy were over 200J at −30°V, therefore, it was considered that the brittle fracture of the girth welded linepipe unlikely occur at reeling and aging situation in this study.

Changes in Tendon Strength After Partial Cut and Effects of Running Peripheral Sutures

2003 ◽  
Vol 28 (5) ◽  
pp. 478-482 ◽  
Author(s):  
J. TAN ◽  
B. WANG ◽  
B. TAN ◽  
Y. XU ◽  
J. B. TANG
Keyword(s):  
Tensile Strength ◽  
Tensile Properties ◽  
Ultimate Strength ◽  
The Other ◽  
Flexor Digitorum Profundus ◽  
Gap Formation ◽  
Load To Failure ◽  
Flexor Digitorum ◽  
Lower Tensile Strength

We performed a study to evaluate the tensile properties of partial tendon lacerations and the effects of peripheral sutures on the tendon strength. Seventy-two fresh pig flexor digitorum profundus tendons were divided equally into eight groups. Tendons in four of the groups were subjected to partial lacerations (60%, 70%, 80%, and 90%) and were not repaired. In the other four similar groups partial lacerations were repaired with running peripheral sutures. The tendons were subjected to load-to-failure tests in an Instron tensile machine to determine the initial, 1 mm, 2 mm gap formation forces and the ultimate strength. The tendons with lacerations of 80% and 90% had a remarkably lower tensile strength than those 60% and 70% lacerations. Running peripheral sutures increased the gap formation forces and the ultimate strength of all the tendons, though particularly those with 80% and 90% lacerations.

Metal–organic frameworks to satisfy gas upgrading demands: fine-tuning thesoc-MOF platform for the operative removal of H2S

2017 ◽  
Vol 5 (7) ◽  
pp. 3293-3303 ◽  
Author(s):  
Youssef Belmabkhout ◽  
Renjith S. Pillai ◽  
Dalal Alezi ◽  
Osama Shekhah ◽  
Prashant M. Bhatt ◽  
...  
Keyword(s):  
Gas Separation ◽  
Metal Organic Frameworks ◽  
Fine Tuning ◽  
Operative Removal ◽  
Metal Organic ◽  
Structure Properties

Structure/properties relationships for a series of isostructural (MOFs) with thesoctopology were explored for various gas separation applications.

Study on Preparation and Property of Drug Loading of AZM-PCL Nanoparticels

2011 ◽  
Vol 121-126 ◽  
pp. 1764-1768
Author(s):  
Li Li Ruan ◽  
Da Xin Wang ◽  
You Wei Zhang ◽  
Jiong Xin Zhao ◽  
Min Wu Wang ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Size Distribution ◽  
Organic Solvents ◽  
Drug Loading ◽  
Average Diameter ◽  
Preparation Condition ◽  
The Other ◽  
Distribution Index ◽  
Model Drug ◽  
Better Than

This study was to prepare polycaprolactone (PCL) nanoparticles. The biodegradable PCL was used as the carrier, and Azithromycin (AZM) was used as the model drug. AZM-PCL nanoparticles (AZM-PCL-NPS) were prepared by desolvation method. The effect of preparation condition: concentration of PCL, molecular weight of PCL, organic solvents, dosage ratio and so on, were specially noted and compared. A homogeneous size distribution and good dispersion were observed, the average diameter was around 70~400 nm, and the distribution index was 0.036~0.136. The drug loading reached 27.69 %, and the efficiency of encapsulation reached as high as 93.25%. The results were better than the other similar researches, this preparation way was successful.

scholarly journals Development of α - β type titanium alloy Ti-4.5Al-2.5Cr-1.2Fe-0.1C-0.3Cu-0.3Ni having good forgeability and machinability

2020 ◽  
Vol 321 ◽  
pp. 11073
Author(s):  
Takashi KONNO ◽  
Keitaro TAMURA ◽  
Yoshio ITSUMI ◽  
Kohei YOKOCHI ◽  
Koichi AKAZAWA ◽  
...  
Keyword(s):  
Titanium Alloy ◽  
Tensile Properties ◽  
Tool Life ◽  
Hot Deformation ◽  
Room Temperature ◽  
The Other ◽  
Total Cost ◽  
Alloy Addition ◽  
Alpha Beta ◽  
Deformation Stress

Development of a titanium alloy having excellent hot forgeability and machinability while having the same properties as Ti-64 alloy is effective in reducing the total cost of titanium parts. To develop a new alpha-beta type titanium alloy which has good hot forgeability, machinability and tensile properties equivalent to those of Ti-64 alloy at room temperature, Ti-4.5Al-2.5Cr-1.2Fe-0.1C-nCu-nNi (n=0 to 2) were prepared and evaluated. The new alloy showed tensile properties equivalent to that of Ti-64 alloy at room temperature. On the other hand, the hot deformation stress of new alloy was about 30% lower than that of Ti-64 alloy, and the excellent deformability was confirmed. The addition of Cu and Ni to Ti-4.5Al-2.5Cr-1.2Fe-0.1C alloy suppressed the amount of wear of tool and improved the machinability. Tool life of new alloy machining is extended by about 1.5 times compared to that of Ti-64 alloy. Addition of Cu and Ni is considered to reduce the reactivity between tool and workpiece and improve machinability.

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