scholarly journals Durability-Aimed Design Criteria of Cement-Stabilized Loess Subgrade for Railway

2021 ◽  
Vol 11 (11) ◽  
pp. 5061
Author(s):  
Fuyu Wang ◽  
Weichen Pang ◽  
Xingyuan Qin ◽  
Leilei Han ◽  
Yingjun Jiang
Keyword(s):  
Dynamic Strength ◽  
Strength Reduction ◽  
Design Criteria ◽  
Freeze Thaw ◽  
Long Term Stability ◽  
Railway Construction ◽  
Critical Dynamic ◽  
Strength Design Criteria ◽  
Safety And Stability

The subgrade is the foundation of railway construction, so its strength and stability are very important to ensure the safety and stability of a train. Loess is widely distributed in northwestern China, and it must be stabilized before being used in railway subgrade construction because loess is sensitive to water. Railway subgrade withstands not only the train load but also repeated attacks from the environment and climate because it has to be exposed to natural environment after construction. Therefore, the strength of cement-stabilized loess deteriorates continuously because of the above factors. Taking account of long-term stability, the influences of load on the cement-stabilized loess as well as the strength reduction laws of cement-stabilized loess under wet–dry cycling and freeze–thaw cycling were analyzed in this study. Additionally, the respective reduction coefficients were obtained. Finally, the strength design criteria of cement-stabilized loess subgrade were put forward based on railway subgrade durability by analyzing the obtained reduction coefficients and the critical dynamic strength of railway subgrade.

scholarly journals Preservation of rutin nanosuspensions without the use of preservatives

2019 ◽  
Vol 10 ◽  
pp. 1902-1913 ◽  
Author(s):  
Pascal L Stahr ◽  
Cornelia M Keck
Keyword(s):  
Microbial Contamination ◽  
Good Alternative ◽  
Freeze Thaw ◽  
Long Term Stability ◽  
Universal Approach ◽  
Poorly Soluble ◽  
Microbial Stability ◽  
Preservative Free ◽  
Excellent Stability

Nanocrystals are used as universal approach to improve the bioactivity of poorly soluble active ingredients. They are produced by various techniques, typically yielding aqueous nanosuspensions, which are prone to microbial contamination. Preservation of nanocrystals is possible but might not always be feasible, as preservatives might interfere with other excipients in the formulations or with chemicals used in assays, cell cultures or animal models. Therefore, to enable an easier use of nanocrystals, preservative-free nanosuspensions would be a good alternative. In this study, rutin nanocrystals were frozen and stored for three months at −20 °C. The chemical, physical and microbial stability were monitored, and the results were compared to preserved nanosuspensions. The frozen nanosuspensions remained stable and possessed excellent stability over the whole time of storage, indicating that the freeze–thaw process is suitable for the production of preservative-free nanosuspensions with excellent long-term stability. The freeze–thaw process for nanosuspensions is a simple concept and is suggested as alternative, when preserved nanosuspensions cannot be used.

Freeze-thaw stability and long-term stability of 84 synthetic cannabinoids in serum

2016 ◽  
Vol 9 (10) ◽  
pp. 1506-1511 ◽  
Author(s):  
Cornelius Hess ◽  
Lynn Krueger ◽  
Michael Unger ◽  
Burkhard Madea
Keyword(s):  
Synthetic Cannabinoids ◽  
Freeze Thaw ◽  
Term Stability ◽  
Long Term Stability

scholarly journals Dynamic Strength and Accumulated Plastic Strain Development Laws and Models of the Remolded Red Clay under Long-Term Cyclic Loads: Laboratory Test Results

2015 ◽  
Vol 22 (s1) ◽  
pp. 89-94 ◽  
Author(s):  
Jian Li ◽  
Shanxiong Chen ◽  
Lingfa Jiang
Keyword(s):  
Plastic Strain ◽  
High Speed ◽  
Dynamic Strength ◽  
Confining Pressure ◽  
Red Clay ◽  
Fitting Method ◽  
Laboratory Test Results ◽  
Critical Dynamic ◽  
Curve Fitting Method

Abstract The dynamic strength and accumulated plastic strain are two important parameters for evaluating the dynamic response of soil. As a special clay, the remolded red clay is often used as the high speed railway subgrade filling, but studies on its dynamic characteristics are few. For a thorough analysis of the suitability of the remolded red clay as the subgrade filling, a series of long-term cyclic load triaxial test under different load histories are carried out. Considering the influence of compactness, confining pressure, consolidation ratio, vibration frequency and dynamic load to the remolded red clay dynamic property, the tests obtain the development curves of the dynamic strength and accumulated plastic strain under different test conditions. Then, through curve fitting method, two different hyperbolic models respectively for the dynamic strength and accumulated plastic strain are built, which can match the test datum well. By applying the dynamic strength model, the critical dynamic strength of the remolded red clay are gained. Meanwhile, for providing basic datum and reference for relevant projects, all key parameters for the dynamic strength and accumulated plastic strain of the remolded red clay are given in the paper.

Long-term stability of temocillin in dextrose 5% and in sodium chloride 0.9% polyolefin bags at 5±3°C after freeze-thaw treatment

2011 ◽  
Vol 69 (6) ◽  
pp. 296-301 ◽  
Author(s):  
C. Rolin ◽  
J.-D. Hecq ◽  
P. Tulkens ◽  
D. Vanbeckbergen ◽  
J. Jamart ◽  
...  
Keyword(s):  
Sodium Chloride ◽  
Freeze Thaw ◽  
Term Stability ◽  
Long Term Stability

Stability and Change in Emotional Intelligence: Exploring the Transition to Young Adulthood

2005 ◽  
Vol 26 (2) ◽  
pp. 100-106 ◽  
Author(s):  
James D.A. Parker ◽  
Donald H. Saklofske ◽  
Laura M. Wood ◽  
Jennifer M. Eastabrook ◽  
Robyn N. Taylor
Keyword(s):  
High School ◽  
Emotional Intelligence ◽  
Postsecondary Education ◽  
Life Transition ◽  
Full Time ◽  
Major Life ◽  
Long Term Stability ◽  
Time Period ◽  
Transition From High School

Abstract. The concept of emotional intelligence (EI) has attracted growing interest from researchers working in various fields. The present study examined the long-term stability (32 months) of EI-related abilities over the course of a major life transition (the transition from high school to university). During the first week of full-time study, a large group of undergraduates completed the EQ-i:Short; 32 months later a random subset of these students (N = 238), who had started their postsecondary education within 24 months of graduating from high school, completed the measures for a second time. The study found EI scores to be relatively stable over the 32-month time period. EI scores were also found to be significantly higher at Time 2; the overall pattern of change in EI-levels was more than can be attributed to the increased age of the participants.

Multi-Center Calibration of the Second Reference Material for Thromboplastin, Rabbit, Plain, Coded CRM 149R

1991 ◽  
Vol 65 (03) ◽  
pp. 263-267 ◽  
Author(s):  
A M H P van den Besselaar ◽  
R M Bertina
Keyword(s):  
Reference Material ◽  
Standard Error ◽  
Standard Errors ◽  
Sensitivity Index ◽  
Long Term Stability ◽  
Significant Bias ◽  
The Mean ◽  
The Relationship ◽  
International Sensitivity Index

SummaryIn a collaborative trial of eleven laboratories which was performed mainly within the framework of the European Community Bureau of Reference (BCR), a second reference material for thromboplastin, rabbit, plain, was calibrated against its predecessor RBT/79. This second reference material (coded CRM 149R) has a mean International Sensitivity Index (ISI) of 1.343 with a standard error of the mean of 0.035. The standard error of the ISI was determined by combination of the standard errors of the ISI of RBT/79 and the slope of the calibration line in this trial.The BCR reference material for thromboplastin, human, plain (coded BCT/099) was also included in this trial for assessment of the long-term stability of the relationship with RBT/79. The results indicated that this relationship has not changed over a period of 8 years. The interlaboratory variation of the slope of the relationship between CRM 149R and RBT/79 was significantly lower than the variation of the slope of the relationship between BCT/099 and RBT/79. In addition to the manual technique, a semi-automatic coagulometer according to Schnitger & Gross was used to determine prothrombin times with CRM 149R. The mean ISI of CRM 149R was not affected by replacement of the manual technique by this particular coagulometer.Two lyophilized plasmas were included in this trial. The mean slope of relationship between RBT/79 and CRM 149R based on the two lyophilized plasmas was the same as the corresponding slope based on fresh plasmas. Tlowever, the mean slope of relationship between RBT/79 and BCT/099 based on the two lyophilized plasmas was 4.9% higher than the mean slope based on fresh plasmas. Thus, the use of these lyophilized plasmas induced a small but significant bias in the slope of relationship between these thromboplastins of different species.

Sign in / Sign up

Export Citation Format

Share Document