Ramie Fiber Modification Trials under Different Conditions

2012 ◽  
Vol 268-270 ◽  
pp. 245-249
Author(s):  
Qi Rui Wang ◽  
Wei Fan
Keyword(s):  
Mass Loss ◽  
Degradation Rate ◽  
Microbial Growth ◽  
Loss Rate ◽  
Mass Loss Rate ◽  
Biological Properties ◽  
Anaerobic Sludge ◽  
Ramie Fiber ◽  
Fiber Modification ◽  
Silane Coupling

The test studied three ways of modification effect for ramie fiber, included PVC coated, MMA graft and silane coupling. Also the diverse factors for modification were explored under the situations of hydrophilicity, biodegradability and parasitotropism. The results showed that: All modified ways for KH-570 silane coupling, PVC coated, and MMA graft could reduce bibulous rate of ramie fiber effectively, which PVC coated was best (10.42 %), while bibulous rate of MMA graft was 10.56 %. Both of all were lower than the bibulous rate of unmodified (4-5 %). Then soaked in conditions of distilled water, anaerobic sludge and anaerobic sludge, the mass loss unmodified were largest, loss of minimum were MMA grafting, MMA grafting and KH-570 coupling, with the mass loss rate were 11.67 %,21.23 % and 22.73%,respectively. With the situation of high salt concentration, the modified fiber degraded significantly that all of the degradation rate were lower than 8%. The biological properties of ramie fiber were effectively enhanced by modification way of MMA grafted, in aspects of hydrophilicity, biodegradability. Under the condition of MMA grafting, microbial growth and purifying effect, the service life of the fiber was prolonged efficacious.

Combustion of Bio-Coke (Highly Densified Biomass Fuel) Block in High-Temperature Air Flow

2011 ◽  
Author(s):  
Hiroyuki Ito ◽  
Yuto Sakai ◽  
Tamio Ida ◽  
Yuji Nakamura ◽  
Osamu Fujita
Keyword(s):  
High Temperature ◽  
Temperature Distribution ◽  
Mass Loss ◽  
Air Temperature ◽  
Degradation Rate ◽  
Loss Rate ◽  
Ignition Delay Time ◽  
Mass Loss Rate ◽  
Air Flow ◽  
Air Flow Rate

Bio-coke (BIC, highly densified biomass briquette), a newly developed biomass fuel as an alternative to coal coke which utilized in blast furnace, is employed in this study. This fuel is manufactured in highly compressed and moderate temperature conditions and has advantages in its versatility of biomass resources, high volumetric calorific value and high mechanical strength. Japanese knotweed is chosen as a biomass resource and is shaped into cylinder (48 mm in diameter and 85 mm in length). One of the most important characteristics of BIC is its high apparent density (1300 kg/m3; twice or more than that of an ordinary wood pellet). In the present study, combustion characteristics of a single BIC fuel in high temperature air flow (473–873 K, 550–750 NL/min.) are investigated. Air is preheated and blown to the bottom surface of the BIC. Ignition and subsequent combustion behavior are observed with monitoring gas temperature near the BIC, surface and inside the BIC temperature, and time dependent mass loss of the BIC is measured. In the case with low air temperature, low heat flux from the fuel surface leads to the broad temperature distribution inside the BIC accompanied by the increase in ignition delay time and, then, once ignition takes place degradation rate becomes larger than the case with high temperature air. On the other hand, mass loss rate for the case of solid surface combustion in the high temperature air does not depend on the air temperature but does depend on the air flow rate, which is a result of reduced degradation rate relating to narrow temperature distribution in depth caused by short ignition delay time. Consequently, it is suggested that the history of preheating, i.e. the preheated condition which is determined by air temperature and air flow rate, is an essential factor to determine the ignition mode in the early stage of BIC combustion and the mass burning velocity in the period of main combustion with flame. It is found that the mass loss rate of BIC in the gas-phase combustion period increases with decrease in supplied air temperature in this study.

scholarly journals SN 2009ip: CONSTRAINTS ON THE PROGENITOR MASS-LOSS RATE

2013 ◽  
Vol 768 (1) ◽  
pp. 47 ◽  
Author(s):  
E. O. Ofek ◽  
L. Lin ◽  
C. Kouveliotou ◽  
G. Younes ◽  
E. Göğüş ◽  
...  
Keyword(s):  
Mass Loss ◽  
Loss Rate ◽  
Mass Loss Rate

Effect of Sample Width on Downward Flame Spread over Typical Energy Conservation Material at a High Elevation Area

2014 ◽  
Vol 664 ◽  
pp. 199-203 ◽  
Author(s):  
Wei Guang An ◽  
Lin Jiang ◽  
Jin Hua Sun ◽  
K.M. Liew
Keyword(s):  
Mass Loss ◽  
Flame Spread ◽  
Loss Rate ◽  
Mass Loss Rate ◽  
High Elevation ◽  
Flame Height ◽  
Spread Rate ◽  
Flame Spread Rate ◽  
Sample Width ◽  
Downward Flame Spread

An experimental study on downward flame spread over extruded polystyrene (XPS) foam at a high elevation is presented. The flame shape, flame height, mass loss rate and flame spread rate were measured. The influences of width and high altitude were investigated. The flame fronts are approximately horizontal. Both the intensity of flame pulsation and the average flame height increase with the rise of sample width. The flame spread rate first drops and then rises with an increase in width. The average flame height, mass loss rate and flame spread rate at the higher elevation is smaller than that at a low elevation, which demonstrates that the XPS fire risk at the higher elevation area is lower. The experimental results agree well with the theoretical analysis. This work is vital to the fire safety design of building energy conservation system.

scholarly journals Radio Supernovae as Direct Evidence of Stellar Evolution in Real Time

1998 ◽  
Vol 11 (1) ◽  
pp. 367-367
Author(s):  
S.D. Van Dyk ◽  
M.J. Montes ◽  
K.W. Weiler ◽  
R.A. Sramek ◽  
N. Panagia
Keyword(s):  
Mass Loss ◽  
Stellar Evolution ◽  
Loss Rate ◽  
Direct Evidence ◽  
Mass Loss Rate ◽  
X Ray ◽  
Stringent Constraint ◽  
Clear Change ◽  
Late Stages ◽  
Circumstellar Environment

The radio emission from supernovae provides a direct probe of a supernova’s circumstellar environment, which presumably was established by mass-loss episodes in the late stages of the progenitor’s presupernova evolution. The observed synchrotron emission is generated by the SN shock interacting with the relatively high-density circumstellar medium which has been fully ionized and heated by the initial UV/X-ray flash. The study of radio supernovae therefore provides many clues to and constraints on stellar evolution. We will present the recent results on several cases, including SN 1980K, whose recent abrupt decline provides us with a stringent constraint on the progenitor’s initial mass; SN 1993J, for which the profile of the wind matter supports the picture of the progenitor’s evolution in an interacting binary system; and SN 1979C, where a clear change in presupernova mass-loss rate occurred about 104 years before explosion. Other examples, such as SNe 19941 and 1996cb, will also be discussed.

scholarly journals Evolution of the mass-loss rate during atmospheric and pressurized slow pyrolysis of wheat straw in a bench-scale reactor

2018 ◽  
Vol 136 ◽  
pp. 18-26 ◽  
Author(s):  
Gianluca Greco ◽  
María Videgain ◽  
Christian Di Stasi ◽  
Belén González ◽  
Joan J. Manyà
Keyword(s):  
Mass Loss ◽  
Wheat Straw ◽  
Loss Rate ◽  
Mass Loss Rate ◽  
Slow Pyrolysis ◽  
Bench Scale ◽  
Scale Reactor

scholarly journals Environmental Influence on Stellar Evolution: The Horizontal Branch of NGC 1851

1996 ◽  
Vol 174 ◽  
pp. 357-358
Author(s):  
I. Saviane ◽  
G. Piotto ◽  
M. Capaccioli ◽  
F. Fagotto
Keyword(s):  
Mass Loss ◽  
Loss Rate ◽  
Environmental Influence ◽  
Mass Loss Rate ◽  
Bimodal Distribution ◽  
Age Difference ◽  
Horizontal Branch ◽  
Cluster Area ◽  
The Difference ◽  
Red Clump

The bimodal nature of the horizontal branch (HB) of NGC 1851 is known since Stetson (1981). In order to better understand the properties of its HB, we collected a set of data at the ESO-NTT telescope, which provides a full coverage of the cluster area. Additional archive images from the HST-WFPC camera have been used in order to study the central region. The resulting c-m diagram (CMD) for 20500 stars is presented in Fig. 1 (left). Despite its metallicity ([Fe/H]=−1.3), NGC 1851 presents a well defined blue HB tail, besides the expected red clump. The observed CMD has been compared with the synthetic ones. The bimodal HB can be reproduced assuming that there are two stellar populations in the cluster, with an age difference of ∼ 4 Gyr, hypothesis not supported by other properties of the CMD. On the other side, if we assume that the stars in NGC 1851 are 15 Gyr old (as suggested by the difference between the HB and the TO luminosities), only a bimodal mass loss can reproduce the HB morphology: only stars with higher than standard mass loss rate are able to populate the blue-HB (BHB) tail (Fig. 1,left). There are no observational evidences for a bimodal distribution of other parameters (He, CNO, etc.).

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