Extraction, Distribution, and Precipitation Mechanism of TiN–MnS Complex Inclusions in Al-Killed Titanium Alloyed Interstitial Free Steel

Shuai Gao,Min Wang,Jian‑long Guo,Hao Wang,Jian‑guo Zhi,Yan‑ping Bao 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.5

The TiN–MnS complex inclusions in Al-killed titanium alloyed interstitial free steel were extracted from the slabs using anelectrolytic aqueous solution method. Scanning electron microscopy with energy spectroscopy analysis and an automaticscanning electron microscope were employed to analyze the size and distribution of TiN–MnS inclusions in the thicknessdirection of the slab. It was found that TiN–MnS complex inclusions were primarily concentrated in the 1/4 thickness directionfrom the inner and outer surfaces, and the size of the complex inclusions in the slab center was approximately 8 μm.TiN began to precipitate when the solidification rate reached 0.646–0.680 in the δ phase, and MnS would appear in the γphase when the solidification rate exceeded 0.450 through thermodynamic analysis. Also, the formation mechanism of thecomplex TiN–MnS was investigated under a crystal structure during solidification.

Separation of arenols from a low-temperature coal tar by liquid-liquid extraction

Hua-Shuai Gao,Zhi-Min Zong,Zheng Yang,Dao-Guang Teng,Xiu-Hua Sun,Li Yan,Xian-Yong Wei,Qing-Jie Guo,Tian-Sheng Zhao,Hong-Cun Bai 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.5

Low-temperature coal tar (LTCT) is a sticky liquid mixture produced mainly from coal pyrolysis, which contains various value-added chemicals (VACs). Liquid-liquid extraction is considered as one of the green and effective ways to explore the organic composition and separate the VACs from LTCT. Herein, petroleum ether, methanol, and carbon disulfide were used to extract arenols from a LTCT. As a result, the relative content and absolute content of arenols extracted from the LTCT are ca. 96.3% and 85.9%, respectively. Among them, p-cresol is predominant, accounting for 22.2%. The isolated contents of arenols are up to 84.6%. Moreover, a kilogram-scale operation was carried out under the same conditions, which offers a potential application in industrial production.

Effect of In Situ Thermal Stretching during Oxidative Stabilization on the Orientation of Cyclized Ladder Structure and Its Carbon Fiber

Shuai Wu,Ai-jun Gao,Liang-hua Xu 한국섬유공학회 2018 Fibers and polymers Vol.19 No.6

The effect of in situ thermal stretching during oxidative stabilization on the orientation of cyclized ladder structure was investigated. Based on the structure evolution of PAN fibers with the increasing stabilization temperatures, the stabilization process was classified into three different stages, namely before the onset of cyclization, during cyclization in amorphous region, and during cyclization in crystalline region. The polyacrylonitrile (PAN) precursor fibers were stretched at the three stages with stretching ratios from 0 % to 8 % during continuous stabilization process. The results show that the orientation degree of cyclized ladder structure increases with the increase of stretching ratio at the three stages and the maximum orientation efficiency of cyclized ladder structure is obtained when PAN fibers are stretched at the stage of during cyclization in crystalline region. The orientation of resulting carbon fibers strongly depends on the orientation degree of cyclized ladder structure. The orientation efficiency of turbostratic graphite crystallite also agrees well with that of cyclized ladder structure. Meanwhile, the orientation efficiency of turbostratic graphite crystallite is higher than that of cyclized ladder structure and the difference values between orientation efficiency of the two structures decrease firstly then increase with the increase of degree of cyclization.

Highly efficient and selective extraction of minor bioactive natural products using pure ionic liquids: Application to prenylated flavonoids in licorice

Shuai Ji,Yujie Wang,Shikai Gao,Xian Shao,Wei Cui,Yan Du,Mengzhe Guo,Daoquan Tang 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.80 No.-

Lots of minor constituents in herbal medicines have shown great potential to devolve into leadcompounds, and their extraction is attracting more and more attention in pharmaceutical industry. Thisstudy provided an example that showed efficient and selective extraction of minor bioactive naturalproducts (prenylatedflavonoids with anti-cancer activities) from an herbal medicine (licorice) using pureionic liquids as green solvents. After investigation of a variety of hydrophobic ionic liquids withultrasonic-assisted extraction, we found that [C8MIM]BF4 (1-octyl-3-methylimidazolium tetrafluor-oborate) was the most effective one for extraction offive representative compounds (isoangustone A,glycycoumarin, licoisoflavanone, licoricidin and glabridin), and solvent to solid ratio, extraction time,extraction temperature and soaking time were then optimized through single-factor experiments andresponse surface methodology. As a result, the established method had significantly higher extractionselectivity than conventional organic solvents, which could be attributed to significant physical change oflicorice microstructures after extraction, as well as strong interactions (especially hydrogen bondinteractions) between [C8MIM]BF4 and prenylatedflavonoids by mechanism study. In addition, 78.92% ofthe extracted prenylatedflavonoids could be readily recovered from [C8MIM]BF4 by using reversed-phasesolid phase extraction, and the recyclability of [C8MIM]BF4 was also confirmed.

Extraction and phase transformation of iron in fine-grained complex hematite ore by suspension magnetizing roasting and magnetic separation

Shuai Yuan,Ruofeng Wang,Qi Zhang,Yanjun Li,Peng Gao 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.7

Suspension magnetizing roasting-magnetic separation technology was used to extract iron from fine-grainedcomplex hematite ore. The effect of roasting conditions on the magnetizing roasting-magnetic separation process wasstudied. In summary, a concentrate with TFe grade of 69.96% and Fe recovery of 79.02% could be obtained under conditionsof a roasting temperature of 500 oC, roasting time was 12 min, reductant concentration of 30%, and total gasflow of 200mL/min, while TFe grade of final tailings was 5.66%. The phase composition and X-ray photoelectronspectroscopy analysis showed that hematite in the sample was transformed into magnetite during suspension magnetizationroasting. After roasting, the proportion of Fe content in the phase of the magnetite increased from 5.91% inroasting feed to 97.96% in the roasting product. Transmission electron microscopy results also confirmed that hematitewas transformed into magnetite with spinel structure, and the newly formed magnetite had good crystallinity. Scanning electron microscopy and BET analysis showed that roasting could increase the specific surface area, total porevolume, and porosity of the roasted product, which would strengthen the internal diffusion of CO and CO2 in the particles,to improve the reduction rate of hematite. The loose internal structure of roasted particles led to the decrease ofmechanical properties, which was conducive to improving the subsequent grinding efficiency.

<i>Orobanche cernua</i> Loefling Attenuates Ultraviolet B-mediated Photoaging in Human Dermal Fibroblasts

Gao, Wei,Wang, Yu-shuai,Qu, Zheng-yi,Hwang, Eunson,Ngo, Hien T. T.,Wang, Ying-ping,Bae, Jahyun,Yi, Tae-hoo Wiley (Blackwell Publishing) 2018 Photochemistry and photobiology Vol.94 No.4

<P>UV radiation is the primary cause of skin photoaging, which results in an increase in matrix metalloproteinases and degradation of collagen. Developing new natural antioxidant as photoprotective agents has become a popular area of research. Orobanche cernua Loefling is a parasitic plant that is rich in phenylethanoid glycosides (PhGs). This study investigated the photoprotective effects of the ethanolic extract of Orobanche cernua Loefling (OC) and its principal component acteoside on UVB-induced photoaging as well as their underlying molecular mechanisms in normal human dermal fibroblasts (NHDFs). Biological testing demonstrated that OC and acteoside possessed significant photoprotective activities, reducing MMP and IL-6 levels while improving type-I procollagen synthesis in UVB-irradiated NHDFs. Further study showed that the protective mechanisms were the improvement of transcription factor Nrf2-mediated antioxidant defensive system, suppression of MAPK/AP-1 and activation of the TGF-/Smad pathway. Together, our results suggested that OC might be a promising antiphotoaging agent against UV radiation-induced skin damage.</P>

A Research on Countermeasures of Shared Bicycles in China

Gao HANG,Shuai SU 한국유통과학회 2018 KODISA ICBE (International Conference on Business Vol.2018 No.-

Under the background of green, low carbon, environmental protection and sustainable development, shared bicycles have achieved a rapid development period, with remarkable achievements and many problems. Shared bicycles have solved the problem of the last mile of city traffic . However, this new thing still faces many problems such as lack of supervision, industry competition, high cost, low operating efficiency and hidden danger. In order to solve the problems above, we need the cooperation of core stakeholders such as government, industry, enterprises and users.The Problems in the Development of Shared Bicycles in China: Firstly,Imperfect Market Supervision Mechanism. Under the constant promotion of internet + and innovation and entrepreneurship, a large number of new business models have emerged in sharing economy. Second, Blind Expansion with Hidden Dangers.Shared bike is favored by the capital market for its convenience and greening of the last mile of travel, and the financing rhythm and the amount of funds are constantly updated. Third, High Operating Costs.The manufacturing cost of shared bicycles is high. Fourth, Disordered Parking and Malicious Damage.The number of market launches of shared bicycles is large, and there is a need for large enough space to park. Fifth, Safety Performance Needs to be Strengthened No new thing, no industry can ignore safety.

Analysis of Circulating Tumor DNA to Predict Neoadjuvant Therapy Effectiveness and Breast Cancer Recurrence

Shuai Hao,Wuguo Tian,Jianjie Zhao,Yi Chen,Xiaohua Zhang,Bo Gao,Yujun He,Donglin Luo 한국유방암학회 2020 Journal of breast cancer Vol.23 No.4

Purpose: Real-time detection and intervention can be used as potential measures to markedly decrease breast cancer mortality. Assessment of circulating tumor DNA (ctDNA) may offer great benefits for the management of breast cancer over time. However, the use of ctDNA to predict the effectiveness of neoadjuvant treatment and recurrence of breast cancer has rarely been studied. Methods: We prospectively recruited 31 breast cancer patients with 4 subtypes. Three time points were set in this study, including before any therapy (C1), during surgery (T), and six months after surgery (C2). We collected peripheral blood samples from all 31 patients at C1, tumor tissue from all 31 patients at T, and peripheral blood samples from 25 patients at C2. Targeted 727-gene panel sequencing was performed on ctDNA from all blood samples and tissue DNA from all tissue samples. Somatic mutations were detected and analyzed using a reference standard pipeline. Statistical analysis was performed to identify possible associations between ctDNA profiles and clinical outcomes. Results: In total, we detected 159, 271, and 70 somatic mutations in 30 C1 samples, 31 T samples, and 12 C2 samples, respectively. We identified specific genes, such as PIK3CA, TP53, and KMT2C, which were highly mutated in the tissue samples. Furthermore, mutated KMT2C observed in ctDNA of the C2 samples may be an indicator of breast cancer recurrence. Conclusion: Our study highlights the potential of ctDNA analysis at different timepoints for assessing tumor progression and treatment effectiveness, as well as prediction of breast cancer recurrence.

Fungal diversity in deep-sea sediments from Magellan seamounts environment of the western Pacific revealed by high-throughput Illumina sequencing

Shuai Yang,Wei Xu,Yuanhao Gao,Xiaoyao Chen,Zhu-Hua Luo 한국미생물학회 2020 The journal of microbiology Vol.58 No.10

There are lots of seamounts globally whose primary production is disproportionally greater than the surrounding areas. Compared to other deep-sea environments, however, the seamounts environment is relatively less explored for fungal diversity. In the present study, we explored the fungal community structure in deep-sea sediments from four different stations of the Magellan seamounts environment by using high-throughput sequencing of the ITS1 region. A total of 1,897,618 ITS1 sequences were obtained. Among these sequences, fungal ITS1 sequences could be clustered into 1,662 OTUs. The majority of these sequences belonged to Ascomycota. In the genera level, the most abundant genus was Mortierella (4.79%), which was reported as a common fungal genus in soil and marine sediments, followed by Umbelopsis (3.80%), Cladosporium (2.98%), Saccharomycopsis (2.53%), Aspergillus (2.42%), Hortaea (2.36%), Saitozyma (2.20%), Trichoderma (2.12%), Penicillium (2.11%), Russula (1.86%), and Verticillium (1.40%). Most of these recovered genera belong to Ascomycota. The Bray-Curtis analysis showed that there was 37 to 85% dissimilarity of fungal communities between each two sediment samples. The Principal coordinates analysis clearly showed variations in the fungal community among different sediment samples. These results suggested that there was a difference in fungal community structures not only among four different sampling stations but also for different layers at the same station. The depth and geographical distance significantly affect the fungal community, and the effect of depth and geographical distance on the structure of the fungal community in the Magellan seamounts is basically same. Most of the fungi were more or less related to plants, these plant parasitic/symbiotic/endophytic fungi constitute a unique type of seamounts environmental fungal ecology, different from other marine ecosystems.

Oxidation of Zhundong subbituminous coal by Fe2+/H2O2 system under mild conditions

Shuai Chen,Wei Zhou,Mingjun Liu,Guangbo Zhao,Qingxi Cao,Bojun Zhao,Kaikai Kou,Jihui Gao 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.4

Oxidation of coal under mild conditions is effective not only to understand the macromolecular network structure of coal but also to produce useful chemicals, allowing more efficient application of coal resources. In this work, the mild oxidation of Zhundong subbituminous coal (ZS) by Fe2+/H2O2 system was carried out under various conditions, including [Fe2+]/[H2O2] molar ratio, temperature, H2O2 concentration and oxidation time. The liquid oxidation products were analyzed using gas chromatography/mass spectrometry (GC/MS), and the chemical structure changes were studied using Fourier transform infrared spectroscopy (FTIR). The results suggest that the oxidation efficiency of ZS with H2O2 is enhanced with the aid of Fe2+. The optimum conditions were determined to be [Fe2+]/[H2O2] molar ratio of 0.00453, H2O2 concentration of 3mol/L, 60 oC and 4 h according to the oxidation conversion rate. In total, 25 compounds were identified, which could be categorized as six group components. Most of them are valuedadded chemicals, and the content of benzene carboxylic acids is the highest among them, making up 29.99% of all group components in total relative content (TRC). -CH2- should be primary bridge connecting the aromatic rings, and alkylene chains linking three aromatic rings are abundant in ZS.