Comparative Investigation on Fracture of Suspension High Voltage Composite Insulators: A Review—Part II: Chemical Properties and Criteria System

2021 ◽  
Vol 37 (4) ◽  
pp. 18-30
Author(s):  
Yanfeng Gao ◽  
Xidong Liang ◽  
Yi Lu ◽  
Jiafu Wang ◽  
Weining Bao ◽  
...  
Keyword(s):  
High Voltage ◽  
Chemical Properties ◽  
Comparative Investigation

scholarly journals Comparative evaluation of wound healing activity of tilvadi ghrita and durva ghrita on diabetic wound model in rats

2019 ◽  
Vol 10 (4) ◽  
pp. 3376-3384
Author(s):  
Shakila Shabbeer Shaikh ◽  
Krishna Murthy ◽  
Rajkumar V. Shete ◽  
Rahul S. Solunke
Keyword(s):  
Wound Healing ◽  
Skin Irritation ◽  
Chemical Properties ◽  
Diabetic Control ◽  
Comparative Investigation ◽  
Diabetic Wound ◽  
Control Groups ◽  
Skin Reactions ◽  
Wound Model ◽  
Wound Healing Activity

Previous studies proved the wound healing potential of Tilvadi Ghrita (TG) and Durva Ghrita (DG) on normal wounds, so this study was conducted to investigate wound healing activity of TG and DG on diabetic wound model in rats. Forty-eight adult female Wistar rats in eight groups were used. Alloxan was used to induce diabetes in diabetic groups. Excision wound was made on the dorsal shaved surface of rats, and then Framycetin sulfate cream (FSC) 10%, TG and DG were applied in control and treatment groups. While in normal control and diabetic control groups, no medication was done. Wound photographs were taken on alternative days to evaluate wound healing. Percentage wound contraction, the effect on wound size, and epithelization period parameters were studied. Ghritas were investigated for their preliminary phytochemicals, Physico-chemical properties, skin irritation test, and wound healing activity in normal and diabetic rats. Data were expressed as mean ± SEM and analyzed using Two-way ANOVA followed by Bonferroni’s multiple range test. Studies revealed that TG and DG do not cause any harmful skin reactions, so both ghritas were found to be safe for topical application. Both formulations showed better and fast healing as compared to untreated normal and diabetic control groups. After comparative investigation, it was observed that DG possesses higher wound healing potential in normal and diabetic groups with comparison to TG. Wound healing action in normal and diabetic wounds, it endowed due to the presence of different phytoconstituents reported in the literature and proved to be beneficial in the management of wounds.

scholarly journals Comparative investigation of the influence of kaolin and dolomite on the properties of polyurethane foam

2021 ◽  
Vol 8 ◽  
pp. 27
Author(s):  
Joseph Ajibade Omotoyinbo ◽  
Isiaka Oluwole Oladele ◽  
Jamiu Mosebolatan Jabar ◽  
Joseph Olatunde Borode ◽  
Kenneth Kanayo Alaneme ◽  
...  
Keyword(s):  
Polyurethane Foam ◽  
System Approach ◽  
Chemical Properties ◽  
Comparative Investigation ◽  
Vibration Band ◽  
The Matrix ◽  
Stretching Vibration ◽  
Sulfonic Acid Groups ◽  
Polyurethane Matrix ◽  
And Chemical Properties

This work investigates the influence of kaolin and dolomite on the properties of polyurethane foam. The selected fillers were pulverized and sieved to obtained < 90 μm that were used as reinforcements in the polyurethane matrix in a randomly dispersed mode. The matrix constituents were mixed in the same ratio while fillers were introduced via a one-shot system approach in predetermined proportions of 3–7 wt.%. The work was carried out to identify optimum fillers to be utilized in the production of polyurethane rigid foams given the effect of the fillers on the physical, mechanical, and chemical properties of the foam. FTIR, XRF, and SEM and mechanical property tests were carried out on the filled polyurethane foam. The presence of the fillers in the foam showed a rupture in the structure of the foams with the cells having similar arrangements. The addition of dolomite and Kaolin degrades the sulfonic acid groups and promoted the appearance of Si–O stretching vibration band. The density, hardness, flexural and compressive strengths of the polyurethane foam were enhanced with the the addition of dolomite and kaolin particles.

Sleep-promoting material from human urine and its relation to factor S from brain

1980 ◽  
Vol 238 (2) ◽  
pp. E116-E123
Author(s):  
J. M. Krueger ◽  
J. Bacsik ◽  
J. Garcia-Arraras
Keyword(s):  
Ion Exchange ◽  
Slow Wave ◽  
High Voltage ◽  
Human Urine ◽  
Time Course ◽  
Slow Wave Sleep ◽  
Gel Filtration ◽  
Chemical Properties ◽  
Intraventricular Infusion ◽  
High Voltage Electrophoresis

A sleep-promoting factor was extracted from human urine. Intraventricular infusion of the purified material induced excess slow-wave sleep in rats and rabbits for 5--10 h after the infusion. Chemical properties of the urinary factor were similar to those of factor S derived from whole brains of sleep-deprived goats, sheep, and rabbits. The behavior of the urinary factor in two ion exchange chromatographic steps, high voltage electrophoresis, gel-filtration, and ultrafiltration was similar to that of factor S. Effects of the purified urinary factor on slow-wave sleep of rats and rabbits were similar in time-course and duration to those of factor S from brain. However, the factor obtained from human urine did not increase the amplitude of cortical slow waves to the same extent as did factor S from brains of sleep-deprived animals.

Variation of surface and bonding properties among four wood species induced by a high voltage electrostatic field (HVEF)

Holzforschung ◽  
2019 ◽  
Vol 73 (10) ◽  
pp. 957-965 ◽  
Author(s):  
Qian He ◽  
Tianyi Zhan ◽  
Haiyang Zhang ◽  
Zehui Ju ◽  
Lu Hong ◽  
...  
Keyword(s):  
High Voltage ◽  
Electrostatic Field ◽  
Wood Species ◽  
Phenol Formaldehyde ◽  
Lignin Content ◽  
Chemical Properties ◽  
Pinus Massoniana ◽  
Populus Tomentosa ◽  
Chinese Fir ◽  
Masson Pine

Abstract A high voltage electrostatic field (HVEF) was applied to enhance the bonding performance of wood composites prepared with phenol-formaldehyde (PF) adhesive and different wood species and radial cut combinations. Four wood species including Masson pine (Pinus massoniana), Chinese fir (Cunninghamia lanceolata), poplar (Populus tomentosa) and ayous (Triplochiton scleroxylon) were studied. The results of HVEF-treatment turn out to be species-dependent, and are related to the anatomical and chemical properties of wood. It was demonstrated by a statistical approach that the lignin content is the most significant parameter with a good correlation coefficient (R2 > 0.8). High lignin content leads to high free radical concentration at the wood surface and the HVEF enhanced the adhesive penetration depth, the maximal density and the bonding strength (Bst) at the interphase. On the contrary, high extract contents and large lumina diameters negatively impacted the surface modification by HVEF. The magnitude of the effects was in the following order: ayous < poplar < Masson pine < Chinese fir.

Comparative investigation of the resistance and ability to trigger high voltage discharge for single and multiple femtosecond filaments in air

2013 ◽  
Vol 22 (3) ◽  
pp. 035203 ◽  
Author(s):  
Kai-Min Guo ◽  
Zuo-Qiang Hao ◽  
Jing-Quan Lin ◽  
Chang-Kai Sun ◽  
Xun Gao ◽  
...  
Keyword(s):  
High Voltage ◽  
Comparative Investigation ◽  
High Voltage Discharge

Degradation of cellulose with high voltage electrons

1978 ◽  
Vol 36 (1) ◽  
pp. 494-495
Author(s):  
P. A. Tucker ◽  
S. P. Hersh ◽  
G. M. Berry ◽  
N. Kerr ◽  
D. M. Mcelwain
Keyword(s):  
Electron Microscopy ◽  
High Voltage ◽  
Chemical Properties ◽  
Cotton Fabrics ◽  
Radiation Doses ◽  
Diffraction Patterns ◽  
Engineering Corporation ◽  
High Voltage Engineering ◽  
Initial Results ◽  
And Chemical Properties

As part of a larger study of the degradation of polymers, cotton cellulose is being intentionally degraded with high voltage electrons. The initial results were reported earlier (1). Because of the implications of this study to the electron microscopy of beam sensitive materials, special attention is being given to relating these studies to electron microscopy.Generally, the microscopist's main, and perhaps only, information on specimen degradation is that provided by diminution of the electron diffraction pattern. It will be shown in this paper that even though specimen diffraction patterns are only slightly altered, the mechanical and chemical properties are vastly changed.To produce degraded fabrics having strength losses of 75% or more, cotton fabrics were exposed to radiation doses of 50 and 100 Mrad at 550 kV in an electron accelerator manufactured by High Voltage Engineering Corporation. Properties of such cotton fabrics before (i.e., control) and after exposure to 50 and 100 Mrad dosages are presented in Table I.

Impact of ultrasounds and high voltage electrical discharges on physico-chemical properties of rapeseed straw’s lignin and pulps

2017 ◽  
Vol 237 ◽  
pp. 11-19 ◽  
Author(s):  
M. Brahim ◽  
B.L. Checa Fernandez ◽  
O. Regnier ◽  
N. Boussetta ◽  
N. Grimi ◽  
...  
Keyword(s):  
High Voltage ◽  
Chemical Properties ◽  
Electrical Discharges ◽  
Physico Chemical

scholarly journals Comparative investigation of 15 Level and 17 level cascaded h-bridge MLI with cross h-bridge MLI fed permanent magnet synchronous motor

2021 ◽  
Vol 21 (2) ◽  
pp. 723
Author(s):  
J. Srinivas Rao ◽  
Suresh Kumar Tummala ◽  
Narasimha Raju Kuthuri
Keyword(s):  
Permanent Magnet ◽  
High Voltage ◽  
Output Voltage ◽  
Permanent Magnet Synchronous Motor ◽  
Harmonic Distortion ◽  
Synchronous Motor ◽  
Comparative Investigation ◽  
Multilevel Inverters ◽  
Series Configuration ◽  
Switching Devices

Multilevel inverters offers eminent solutions to high voltage high power applications due to the association of several devices in a series configuration. In this paper, a comparative investigation of both 15 and 17 level cascaded h-bridge multi level inverter with cross h-bridge fed permanent magnet synchronous motor are presented by appropriate simulations and mathematical analysis. Comparative analysis includes Inverter output voltage and current, number of switching devices, stator current and speed of PMSM and total harmonic distortion levels. Limitation of several switching devices, which can afford high voltage in the inverter is the major problems raised in this study. The advantage of this analysis is to figure out the appropriate inverter that can be used for real time application by considering the factors via. Harmonic distortion, output voltage, current, number of switching devices etc. Validation of the analysis is processed through matlab/simulink platform.

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