Study of using diesel/high-ON biofuel blends as the pilot fuel with large proportion and split injection in the dual-fuel combustion
FUEL
Authors: Meng, Xiangyu; Wang, Junfu; Zhou, Yihui; Tian, Hua; Long, Wuqiang; Bi, Mingshu
Abstract
Dual-fuel combustion using diesel and high-octane number (ON) biofuel of n-butanol blends to ignite compressed natural gas (CNG) with pilot fuel split injection was investigated. 30% n-butanol/70% diesel (B30D70) and pure diesel (B0D100) as the pilot fuels were compared with the start of pre-injection (SOIp) timings swept from -30 (SOI(p)30) to -80 degrees CA ATDC (SOI(p)80) under the CNG substitution rates of 50% at low load and 65% at medium load. A fixed start of main-injection (SOIm) timing of -9 degrees CA ATDC in B0D100 and various SOIm timings in B30D70 to match CA50 of B0D100 were employed. The experimental results indicated that adding n-butanol in the pilot fuel can significantly reduce the PM emission at advanced SOIp timings even with large proportion of pilot fuel. At low load, B30D70 reveals higher indicated thermal efficiency (ITE) due to its shorter combustion duration compared to B0D100, and it also leads to lower NOx emissions resulted from the more homogeneous mixture. The CO and THC emissions tend to be slightly increased in B30D70 for the advanced SOIp timings. At medium load, B30D70 also obtains higher ITE but yields higher NOx emissions. Relatively low level of NOx emissions can be obtained at early SOIp timings, such as SOI(p)60, SOI(p)70 and SOI(p)80. The CO and THC emissions are similar for the two pilot fuels at these timings. For the comparisons of the two pilot fuels and injection strategies, it can be demonstrated that B30D70 is more favorable to the thermal efficiency and emissions with split injection at SOI(p)40 under low load condition and early SOIp timings under medium load condition.
The sensitivity and specificity of serum glycan-based biomarkers for cancer detection
GLYCANS AND GLYCOSAMINOGLYCANS AS CLINICAL BIOMARKERS AND THERAPEUTICS, PT A
Authors: Tang, Yang; Cui, Yidi; Zhang, Shufeng; Zhang, Lijuan
Abstract
Most of clinically used serum biomarkers for cancer detection were established in early 1980s when the Nobel Prize in physiology or medicine was awarded for the "discovery of the principle for the production of monoclonal antibodies." Using this "Nobel" technology, various monoclonal antibodies were obtained when different types of cancer cells were injected into mice and the ligands on the cancer cell surface were characterized. Both aberrant glycan structures and aberrant glycan-associated glycoproteins were revealed as a common feature of cancer cell surfaces through the specific interactions with the monoclonal antibodies. These results indicate that the biosynthesis of the environment-sensitive glycan structures goes awry in cancer cells, which is beyond genetic mutations. Later on, the glycan-related biomarkers were detected in the sera of cancer patients and then developed into serum biomarkers, such as CA125, CA153, CA195, CA199, CA242, CA27.29, CA50, and CA724, which are still in clinical use as of today. During the past 30 years, even with the advancement of different OMICS technologies not limited to genomics, epigenomics, proteomics, glycomics, lipidomics, and metabolomics, very few serum biomarkers have been introduced into clinical practice. The reason is that most of the newly discovered cancer biomarkers are inferior in terms of sensitivity and specificity to these biomarkers. We will summarize the reported sensitivity and specificity of currently used cancer biomarkers, especially the glycan-related biomarkers, in the forms of tables and radar plots and discuss the pros and cons of currently used cancer biomarkers.