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In order to use polysilicon cutting waste more efficiently, SiC/α-Si3N4 composite powders were prepared via electromagnetic induction heating at ambient pressure. Factors affecting synthesis and reaction mechanisms of the SiC/α-Si3N4 composite powders were investigated. Results show that the morphology of obtained α-Si3N4 consists of particles equiaxed with diameter in the micron range and one-dimensional Si3N4 nanowires with diameter of tens to hundreds of nanometers and length of up to tens of microns. It was found that the addition of NH4Cl can promote nitridation by controlling reaction temperature and participating in the reaction. In addition, the existence of Fe2O3 impurities was found to be beneficial to the formation of α-Si3N4 in reaction process by removing the SiO2 film from silicon and providing FeSi2 liquid phase as effective pass for vapor phase. Mechanisms used to grow Si3N4-NWs were vapor-solid (VS) and vapor-liquid-solid (VLS) depositions.

Boron doped diamond (BDD) electrode is a promising electrochemical material for detecting dopamine level in the human’s body. In this work, we developed a new doping source - graphite and solid boron oxide powders to synthesize BDD film with microwave plasma chemical vapor deposition, so as to avoid using toxic or corrosive dopants, such as boroethane and trimethylborate. The synthesized BDD film is pinhole free and with high doping density of 8.44 × 1020 cm−3 calculated from the Raman spectroscopy. Subsequently, Au nanospheres were decorated on the surface of BDD film to improve electrochemical performance of the BDD film. The Au nanoparticles modified BDD electrode demonstrates an excellent electrochemical response, a high sensitivity (in the range of 5 μM-1 mM), and a low detection limit (∼ 0.8 μM) for detecting dopamine.

A novel solid electrochemical sulfur sensor based on ZrO2(MgO) as solid electrolyte and CaAl2O4+CaAl4O7 as electrode coating was developed and tested in the carbon-saturated liquid iron at 1773 K. A mixture of chromium and chromium oxide was used as the reference electrode, CaS was allowed to synthesized in situ during the measurement by the CaAl2O4+CaAl4O7 coating on the surface of ZrO2(MgO) solid electrolyte to form the auxiliary electrode with residual CaAl2O4 and CaAl4O7 phase based on the reactions: CaA l 2 O 4 + S = CaS+A l 2 O 3 + [ O ] and CaA l 4 O 7 + S = CaS+2A l 2 O 3 + [ O ] . The sensor behavior in terms of response time, measurement errors, formation mechanism of auxiliary electrode and the lower limit of measurement was discussed in this study. The results indicated that the sulfur sensor showed such a superior sensing performance of theoretical response, which obeyed the Nernst relationship between the sensor EMF output and the natural logarithm of the sulfur concentration, along with the stable, continuous, and reproducible response. The variations of the EMF versus ln[wt% S] was obtained at 1773 K: E ( mV ) = 48 .371n [ wt % S ] + 31 .07 . The lower detection limit of sulfur activity at 1773 K depended on oxygen activity in the liquid iron, a [ S ] = 40 .85 a [ O ] .

The phase evolution, mechanical properties and electrical properties of 8 mol% MgO–ZrO2 (8 Mg-PSZ) with different amounts of TiO2 are characterized using phase, morphological and electrochemical analyses. The mechanisms for mechanical performance improvement and electrical degradation are also investigated. The addition of TiO2 causes lattice distortion, the appearance of Mg-rich phases at the grain boundaries, grain growth and phase transformation in 8 Mg-PSZ. A significant increase in thermal shock resistance and compressive strength is observed in specimens with 0.5 mol% TiO2. The observed behaviors are explained in terms of second phase (Mg-rich phase) toughness and the creation of microcracks caused by phase transformation and the Mg-rich phase formation. These specimens exhibit a decrease in ionic conductivity due to lattice distortion affecting the mobility of oxygen, Mg-rich phase acting as a barrier to the movement of oxygen vacancies, and the presence of a grain boundary liquid phase acting as a barrier to the diffusion of oxygen.

In this study, we performed whole-exome and targeted sequencing on 85 MLL-PTD AML patients. These AMLs have oncogenic tandem duplication of the MLL gene. At least one well-known oncogenic driver mutation was identified in over 90% of the MLL-PTD patients. In line with earlier sequencing studies of other AML subtypes and the TCGA-AML-sequencing project, DNMT3A was the most often mutated epigenetic regulator (25%); IDH1/2 hotspot mutations were identified in 31% of patients. TET family was the third most prominently mutated epigenetic regulator (TET1 (5%), TET2 (16.3%). Mutations of epigenetic regulators also occurred in polycomb-associated proteins (EZH2, ASXL family members), chromatin remodelers (ARID2, ARID1A), genes associated with histone acetylation (CREBBP, EP300, KAT6A, KAT6B) and histone methylation (MLL2, MLL3). Proliferation-related pathway was extensively mutated, with 54 of 80 MLL-PTD patients (67.5%) carrying at least one mutation of proliferative genes. Specifically, FLT3 mutations were found in 46% of patient samples. Notably, some FLT3-ITD patients had more than one type of internal tandem duplication (ITD) insertion, probably reflecting existence of multiple subclones in these leukemias. We found highly prevalent mutations of cohesin genes: STAG2 (16%), SMC1A (6%), SMC3 (1%), RAD21 (1%) and CTCF (6%). Cohesin pathway is more frequently mutated in MLL-PTD patients (26%) than the AML samples from either TCGA (13%) or a meta-analysis of 1000 AML (9.1%). Remarkably, an extremely high proportion of the mutations had a strong tendency to disrupt the coding sequence in STAG2, emphasizing their crucial tumor-suppressor role in this AML subtype (16% in MLL-PTD vs 3% in TCGA-AML. RNA processing pathway was also strikingly altered in MLL-PTD patients. The most prominently mutated genes within this category were the splicing factors. They included U2AF1 (13%, S34F/Y), SRSF2 (3%), SF3A1 (5%), ZRSR2 (3%), DHX15 (1%) and CWC22 (1%). Multiple mutations co-occur with MLL-PTD which are usually acquired in a sequential manner. A potential ordering for acquisition of many mutations include IDH2/DNMT3A/U2AF1/TET2→MLL-PTD→RAS-receptor tyrosine kinase based on the following reasons: #1, real-time-PCR showed that MLL-PTD was absent in remission while mutations of IDH2, DNMT3A, TET2 and U2AF1 were still retained with a high VAF. This suggests that MLL-PTD was acquired after mutations of IDH2, DNMT3A, TET2 and U2AF1; #2, MLL-PTD is highly stable during disease progression as compared with mutations of the RAS-RTK. On the other hand, RAS-RTK mutations frequently exist as subclonal mutations and tend to be unstable during disease progression. These observations support a notion that MLL-PTD was acquired prior to RAS-RTK. Taken together, MLL-PTD is acquired after those remission-persisting, initiating mutations (IDH2, DNMT3A, TET2 and U2AF1), but prior to lesions of the proliferation-related drivers. Citation Format: Lingwen Ding, Qiaoyang Sun, Kar-Tong Tan, Wenwen Chien, Anand Mayakonda, Dechen Lin, Xinyi Loh, Jinfen Xiao, Manja Meggendorfer, Tamara Alpermann, Manoj Garg, Su-Lin Lim, Vikas Madan, Norimichi Hattori, Yasunobu Nagata, Satoru Miyano, Allen Yeoh Eng Juh, Hsin-An Hou, Yan-Yi Jiang, Yan-Yi Jiang, Sumiko Takao, Li-Zhen Liu, Siew-Zhuan Tan, Siew-Zhuan Tan, Michael Lill, Mutsumi Hayashi, Akitoshi Kinoshita, Hagop M. Kantarjian, Steven M. Kornblau, Seishi Ogawa, Torsten Haferlach, Henry Yang, H. Phillip Koeffler. Mutational profiling of MLL-PTD acute myeloid leukemia [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2450. doi:10.1158/1538-7445.AM2017-2450