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1. chinaXiv:201711.02434 [pdf]

A?Machine?Learning?Assisted,?Label-free,?Non-invasive?Approach?for?Somatic?Reprogramming?inInduced?Pluripotent?Stem?Cell?Colony?Formation?Detection?and?Prediction

Fan, K?(Fan, Ke); Zhang, S?(Zhang, Sheng); Zhang, Y?(Zhang, Ying); Lu, J?(Lu, Jun); Holcombe, M?(Holcombe, Mike); Zhang, X?(Zhang, Xiao)
Subjects: Biology >> Ecology

During cellular?reprogramming, the mesenchymal-to-epithelial transition is accompanied by changes?in?morphology, which occur prior to iPSC?colony?formation. The current?approach?for?detecting morphological changes associated with?reprogramming?purely relies on human experiences, which involve intensive amounts of upfront training, human error with limited quality control and batch-to-batch variations. Here, we report?a?time-lapse-based bright-field imaging analysis system that allows us to implement?a?label-free,?non-invasive?approach?to measure morphological dynamics. To automatically analyse and determine iPSC?colony?formation,?a?machine?learning-based classification, segmentation, and statistical modelling system was developed to guide?colony?selection. The system can detect and monitor the earliest cellular texture changes after the induction of?reprogramming?in?human?somatic?cells on day 7 from the 20-24 day process. Moreover, after determining the?reprogramming?process and iPSC?colony?formation?quantitatively,?a?mathematical model was developed to statistically predict the best iPSC selection phase independent of any other resources. All the computational?detection?and?prediction?experiments were evaluated using?avalidation dataset, and biological verification was performed. These algorithm-detected colonies show no significant differences (Pearson Coefficient)?in?terms of their biological features compared to the manually processed colonies using standard molecular approaches.

submitted time 2017-11-17 Hits565Downloads350 Comment 0

2. chinaXiv:201711.00041 [pdf]

Circulating Fluidized Bed Gasification of Low Rank Coal: Influence of O-2/C Molar Ratio on Gasification Performance and Sulphur Transformation

Zhang, H. X.,; Zhang, Y. K., ; Zhu, Z. P. ; Lu, Q. G.
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

To promote the utilization efficiency of coal resources, and to assist with the control of sulphur during gasification and/or downstream processes, it is essential to gain basic knowledge of sulphur transformation associated with gasification performance. In this research we investigated the influence of O-2/C molar ratio both on gasification performance and sulphur transformation of a low rank coal, and the sulphur transformation mechanism was also discussed. Experiments were performed in a circulating fluidized bed gasifier with O-2/C molar ratio ranging from 0.39 to 0.78 mol/mol. The results showed that increasing the O-2/C molar ratio from 0.39 to 0.78 mol/mol can increase carbon conversion from 57.65% to 91.92%, and increase sulphur release ratio from 29.66% to 63.11%. The increase of O-2/C molar ratio favors the formation of H2S, and also favors the retained sulphur transforming to more stable forms. Due to the reducing conditions of coal gasification, H2S is the main form of the released sulphur, which could be formed by decomposition of pyrite and by secondary reactions. Bottom char shows lower sulphur content than fly ash, and mainly exist as sulphates. X-ray photoelectron spectroscopy (XPS) measurements also show that the intensity of pyrite declines and the intensity of sulphates increases for fly ash and bottom char, and the change is more obvious for bottom char. During CFB gasification process, bigger char particles circulate in the system and have longer residence time for further reaction, which favors the release of sulphur species and can enhance the retained sulphur transforming to more stable forms.

submitted time 2017-11-02 From cooperative journals:《热科学学报》 Hits422Downloads227 Comment 0

3. chinaXiv:201706.00731 [pdf]

Effect of Marangoni Number on Thermocapillary Convection and Free-Surface Deformation in Liquid Bridges

Zhang, Y [ 1 ]; Huang, HL [ 1 ]; Zhou, XM [ 2 ]; Zhu, GP [ 1 ]; Zou, Y [ 1 ]
Subjects: Dynamic and Electric Engineering >> Engineering Thermophysics

Floating zone technique is a crucible-free process for growth of high quality single crystals. Unstable thermocapillary convection is a typical phenomenon during the process under microgravity. Therefore, it is very important to investigate the instability of thermocapillary convection in liquid bridges with deformable free-surface under microgravity. In this works, the Volume of Fluid (VOF) method is employed to track the free-surface movement. The results are presented as the behavior of flow structure and temperature distribution of the molten zone. The impact of Marangoni number (Ma) is also investigated on free-surface deformation as well as the instability of thermocapillary convection. The free-surface exhibits a noticeable axisymmetric (but it is non-centrosymmetric) and elliptical shape along the circumferential direction. This specific surface shape presents a typical narrow 'neck-shaped' structure with convex at two ends of the zone and concave at the mid-plane along the axial direction. At both theta = 0 degrees and theta = 90 degrees, the deformation ratio increases rapidly with Ma at first, and then increases slowly. Moreover, the hydrothermal wave number m and the instability of thermocapillary convection increase with Ma.

submitted time 2017-06-22 From cooperative journals:《热科学学报》 Hits528Downloads261 Comment 0

4. chinaXiv:201705.00514 [pdf]

A co-confined carbonization approach to aligned nitrogen-doped mesoporous carbon nanofibers and its application as an adsorbent

Chen, AB [Chen, Aibing][ 1 ]; Liu, C [Liu, Chao][ 2 ]; Yu, YF [Yu, Yifeng][ 1 ]; Hu, YQ [Hu, Yongqi][ 1 ]; Lv, HJ [Lv, Haijun][ 1 ]; Zhang, Y [Zhang, Yue][ 1 ]; Shen, SF [Shen, Shufeng][ 1 ]; Zhang, J [Zhang, Jian][ 3 ]
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

Nitrogen-doped carbon nanofibers (MCNFs) with an aligned mesoporous structure were synthesized by a co-confined carbonization method using anodic aluminum oxide (AAO) membrane and tetraethy- lorthosilicate (TEOS) as co-confined templates and ionic liquids as the precursor. The as-synthesized MCNFs with the diameter of 80–120 nm possessed a bulk nitrogen content of 5.3 wt% and bimodal meso- porous structure. The nitrogen atoms were mostly b